485BPOS

Registration No. 2-69719

File No. 811-3105

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC  20549

FORM N-1A

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933	x
Pre-Effective Amendment No. __	¨
Post-Effective Amendment No. 66	x
and/or
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	x
Amendment No. 59	x

OPPENHEIMER CAPITAL APPRECIATION FUND

(Exact Name of Registrant as Specified in Charter)

6803 South Tucson Way, Centennial, Colorado 80112-3924

(Address of Principal Executive Offices)                 (Zip Code)

(303) 768-3200

(Registrant’s Telephone Number, including Area Code)

Arthur S. Gabinet, Esq.

OFI Global Asset Management, Inc.

225 Liberty Street, New York, New York 10281-1008

(Name and Address of Agent for Service)

It is proposed that this filing will become effective (check appropriate box):

x Immediately upon filing pursuant to paragraph (b)

¨ On ____________, pursuant to paragraph (b)

¨ 60 days after filing, pursuant to paragraph (a)(1)

¨ On _____________, pursuant to paragraph (a)(1)

¨ 75 days after filing, pursuant to paragraph (a)(2)

¨ On ______________, pursuant to paragraph (a)(2) of Rule 485.

If appropriate, check the following box:

¨ This post-effective amendment designates a new effective date for a previously filed post-effective amendment.

 

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all the requirements for effectiveness of this Registration Statement pursuant to Rule 485(b) under the Securities Act of 1933 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York and State of New York on the 13^th day of January, 2015.

OPPENHEIMER CAPITAL APPRECIATION FUND
By:	Arthur P. Steinmetz *
	Arthur P. Steinmetz President and
	Principal Executive Officer

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed below by the following persons in the capacities on the dates indicated:

Signatures	Title	Date
Brian F. Wruble*	Chairman of the	January 13, 2015
Brian F. Wruble	Board of Trustees
Arthur P. Steinmetz*	President and	January 13, 2015
Arthur P. Steinmetz	Principal Executive Officer
Brian W. Wixted*	Treasurer, Principal	January 13, 2015
Brian W. Wixted	Financial & Accounting Officer
David K. Downes*	Trustee	January 13, 2015
David K. Downes
Matthew P. Fink*	Trustee	January 13, 2015
Matthew P. Fink
Edmund P. Giambastiani, Jr.*	Trustee	January 13, 2015
Edmund P. Giambastiani, Jr.
William F. Glavin, Jr.*	Trustee	January 13, 2015
William F. Glavin, Jr.
Elizabeth Krentzman*	Trustee	January 13, 2015
Elizabeth Krentzman
Mary F. Miller*	Trustee	January 13, 2015
Mary F. Miller
Joel W. Motley*	Trustee	January 13, 2015
Joel W. Motley
Joanne Pace*	Trustee	January 13, 2015
Joanne Pace
Daniel Vandivort*	Trustee	January 13, 2015
Daniel Vandivort
Peter I. Wold*	Trustee	January 13, 2015
Peter I. Wold

*By:	/s/ Mitchell J. Lindauer
	Mitchell J. Lindauer, Attorney-in-Fact

 

EXHIBIT INDEX

Exhibit No.	Description
Ex-101.INS	XBRL Instance Document
Ex-101.SCH	XBRL Taxonomy Extension Schema Document
Ex-101.CAL	XBRL Taxonomy Extension Calculation Linkbase Document
Ex-101.DEF	XBRL Taxonomy Extension Definition Linkbase
Ex-101.LAB	XBRL Taxonomy Extension Labels Linkbase
Ex-101.PRE	XBRL Taxonomy Extension Presentation Linkbase Document

XML

Label

Element

Value

Risk/Return:

rr_RiskReturnAbstract

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Investment Objective. The Fund seeks capital appreciation.

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

Fees and Expenses of the Fund. This table describes the fees and expenses that you may pay if you buy and hold or redeem shares of the Fund. You may qualify for sales charge discounts if you (or you and your spouse) invest, or agree to invest in the future, at least $25,000 in certain funds in the Oppenheimer family of funds. More information about these and other discounts is available from your financial professional and in the section "About Your Account" beginning on page 10 of the prospectus and in the sections "How to Buy Shares" beginning on page 43 and "Appendix A" in the Fund's Statement of Additional Information.

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

You may qualify for sales charge discounts if you (or you and your spouse) invest, or agree to invest in the future, at least $25,000 in certain funds in the Oppenheimer family of funds.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 25,000

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

^[1]

Expenses Restated to Reflect Current [Text]

rr_ExpensesRestatedToReflectCurrent

Expenses have been restated to reflect current fees.

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

Example. The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in a class of shares of the Fund for the time periods indicated. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your expenses would be as follows:

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

If shares are redeemed

Expense Example, No Redemption, By Year, Caption [Text]

rr_ExpenseExampleNoRedemptionByYearCaption

If shares are not redeemed

Portfolio Turnover [Text Block]

rr_PortfolioTurnoverTextBlock

Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in the annual fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 67% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

67.00%

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Principal Investment Strategies. The Fund mainly invests in common stocks of "growth companies." Growth companies are companies whose earnings and stock prices are expected to increase at a faster rate than the overall market. These may be newer companies or established companies of any capitalization range that the portfolio manager believes may appreciate in value over the long term. Currently, the Fund primarily focuses on established companies that are similar in size to companies in the S&P 500 Index or the Russell 1000 Growth Index. The Fund primarily invests in securities of U.S. issuers but may also invest in foreign securities. The portfolio manager looks for growth companies with stock prices that he believes are reasonable in relation to overall stock market valuations. In seeking broad diversification of the Fund's portfolio among industries and market sectors, the portfolio manager focuses on a number of factors that may vary in particular cases and over time. Currently, the portfolio manager looks for:

• companies in business areas that have above-average growth potential

• companies with growth rates that the portfolio manager believes are sustainable over time

• stocks with reasonable valuations relative to their growth potential.

The Fund may sell the stocks of companies that the portfolio manager believes no longer meet the above criteria, but is not required to do so.

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Principal Risks. The price of the Fund's shares can go up and down substantially. The value of the Fund's investments may change because of broad changes in the markets in which the Fund invests or because of poor investment selection, which could cause the Fund to underperform other funds with similar investment objectives. There is no assurance that the Fund will achieve its investment objective. When you redeem your shares, they may be worth more or less than what you paid for them. These risks mean that you can lose money by investing in the Fund.

Risks of Investing in Stock. The value of the Fund's portfolio may be affected by changes in the stock markets. Stock markets may experience significant short-term volatility and may fall sharply at times. Different stock markets may behave differently from each other and U.S. stock markets may move in the opposite direction from one or more foreign stock markets.

The prices of individual stocks generally do not all move in the same direction at the same time and a variety of factors can affect the price of a particular company's stock. These factors may include, but are not limited to: poor earnings reports, a loss of customers, litigation against the company, general unfavorable performance of the company's sector or industry, or changes in government regulations affecting the company or its industry.

Industry and Sector Focus . At times the Fund may increase the relative emphasis of its investments in a particular industry or sector. The prices of stocks of issuers in a particular industry or sector may go up and down in response to changes in economic conditions, government regulations, availability of basic resources or supplies, or other events that affect that industry or sector more than others. To the extent that the Fund increases the relative emphasis of its investments in a particular industry or sector, its share values may fluctuate in response to events affecting that industry or sector. To some extent that risk may be limited by the Fund's policy of not concentrating its investments in any one industry.

Risks of Growth Investing. If a growth company's earnings or stock price fails to increase as anticipated, or if its business plans do not produce the expected results, its securities may decline sharply. Growth companies may be newer or smaller companies that may experience greater stock price fluctuations and risks of loss than larger, more established companies. Newer growth companies tend to retain a large part of their earnings for research, development or investments in capital assets. Therefore, they may not pay any dividends for some time. Growth investing has gone in and out of favor during past market cycles and is likely to continue to do so. During periods when growth investing is out of favor or when markets are unstable, it may be more difficult to sell growth company securities at an acceptable price. Growth stocks may also be more volatile than other securities because of investor speculation.

Who Is The Fund Designed For? The Fund is designed primarily for investors seeking capital appreciation over the long term. Those investors should be willing to assume the risks of short-term share price fluctuations that are typical for a fund focusing on stocks. Because of its focus on long-term growth, the Fund may be more appropriate for investors with longer term investment goals. The Fund is not designed for investors needing current income. The Fund is not a complete investment program. You should carefully consider your own investment goals and risk tolerance before investing in the Fund.

An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

The price of the Fund's shares can go up and down substantially. The value of the Fund's investments may change because of broad changes in the markets in which the Fund invests or because of poor investment selection, which could cause the Fund to underperform other funds with similar investment objectives. There is no assurance that the Fund will achieve its investment objective. When you redeem your shares, they may be worth more or less than what you paid for them. These risks mean that you can lose money by investing in the Fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The Fund's Past Performance. The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance (for Class A shares) from calendar year to calendar year and by showing how the Fund's average annual returns for the periods of time shown in the table compare with those of a broad measure of market performance. The Fund's past investment performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More recent performance information is available by calling the toll-free number on the back of this prospectus and on the Fund's website: https://www.oppenheimerfunds.com/fund/CapitalAppreciationFund

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and taxes are not included and the returns would be lower if they were.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Sales charges and taxes are not included and the returns would be lower if they were. During the period shown, the highest return for a calendar quarter was 18.94% (2nd Qtr 09) and the lowest return was -28.10% (4th Qtr 08). For the period from January 1, 2014 to September 30, 2014 the cumulative return before sales charges and taxes was 9.47%.

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns for the periods ended December 31, 2013

Performance Table Narrative

rr_PerformanceTableNarrativeTextBlock

The following table shows the average annual total returns for each class of the Fund's shares. After-tax returns are calculated using the highest individual federal marginal income tax rates and do not reflect the impact of state or local taxes. Your actual after-tax returns, depending on your individual tax situation, may differ from those shown and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for only one class and after-tax returns for other classes will vary.

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the highest individual federal marginal income tax rates and do not reflect the impact of state or local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Your actual after-tax returns, depending on your individual tax situation, may differ from those shown and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

The Fund's past investment performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

After-tax returns are shown for only one class and after-tax returns for other classes will vary.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

https://www.oppenheimerfunds.com/fund/CapitalAppreciationFund

S&P 500 Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

32.39%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

17.94%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

7.41%

S&P 500 Index  (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

23.93%

^[2]

Russell 1000 Growth Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

33.48%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

20.39%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

7.83%

Russell 1000 Growth Index  (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

24.04%

^[2]

Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) imposed on purchases (as % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

0.59%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.07%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

678

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

897

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,134

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,812

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

678

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

897

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,134

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

1,812

Annual Return 2004

rr_AnnualReturn2004

6.46%

Annual Return 2005

rr_AnnualReturn2005

4.70%

Annual Return 2006

rr_AnnualReturn2006

7.51%

Annual Return 2007

rr_AnnualReturn2007

13.76%

Annual Return 2008

rr_AnnualReturn2008

(45.90%)

Annual Return 2009

rr_AnnualReturn2009

43.58%

Annual Return 2010

rr_AnnualReturn2010

9.14%

Annual Return 2011

rr_AnnualReturn2011

(1.57%)

Annual Return 2012

rr_AnnualReturn2012

13.69%

Annual Return 2013

rr_AnnualReturn2013

29.24%

Year to Date Return, Label

rr_YearToDateReturnLabel

For the period from January 1, 2014 to September 30, 2014 the cumulative return before sales charges and taxes was 9.47%.

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

9.47%

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2014

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

highest return for a calendar quarter was 18.94% (2nd Qtr 09)

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

18.94%

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest return was -28.10% (4th Qtr 08)

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(28.10%)

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 22, 1981

1 Year

rr_AverageAnnualReturnYear01

21.81%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

16.39%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

4.65%

Class A | Return After Taxes on Distributions

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

20.57%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

16.13%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

4.48%

Class A | Return After Taxes on Distributions and Sale of Fund Shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

13.30%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

13.28%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

3.70%

Class B

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) imposed on purchases (as % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

5.00%

Management Fees

rr_ManagementFeesOverAssets

0.59%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.82%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

687

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

878

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,194

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,774

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

187

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

578

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

994

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

1,774

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 01, 1995

1 Year

rr_AverageAnnualReturnYear01

23.23%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

16.59%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

4.76%

Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) imposed on purchases (as % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

Management Fees

rr_ManagementFeesOverAssets

0.59%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.82%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

287

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

578

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

994

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,156

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

187

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

578

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

994

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,156

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 01, 1993

1 Year

rr_AverageAnnualReturnYear01

27.25%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

16.86%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

4.46%

Class R

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) imposed on purchases (as % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

0.59%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.32%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

135

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

421

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

728

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,601

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

135

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

421

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

728

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

1,601

Inception Date

rr_AverageAnnualReturnInceptionDate

Mar. 01, 2001

1 Year

rr_AverageAnnualReturnYear01

27.90%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

17.49%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

4.96%

Class Y

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) imposed on purchases (as % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

0.59%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.23%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.82%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

84

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

263

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

457

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,018

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

84

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

263

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

457

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

1,018

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 03, 1997

1 Year

rr_AverageAnnualReturnYear01

29.69%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

18.25%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

5.68%

Class I

Risk/Return:

rr_RiskReturnAbstract

Maximum Sales Charge (Load) imposed on purchases (as % of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

0.59%

Distribution and/or Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.04%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.63%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

65

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

202

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

352

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

789

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

65

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

202

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

352

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 789

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 29, 2011

1 Year

rr_AverageAnnualReturnYear01

29.82%

5 Years (or life of class, if less)

rr_AverageAnnualReturnYear05

21.54%

10 Years (or life of class, if less)

rr_AverageAnnualReturnYear10

[1] Expenses have been restated to reflect current fees.

[2] As of 12/31/11.

XML

(Oppenheimer Capital Appreciation Fund)

Investment Objective. The Fund seeks capital appreciation.

Fees and Expenses of the Fund. This table describes the fees and expenses that you may pay if you buy and hold or redeem shares of the Fund. You may qualify for sales charge discounts if you (or you and your spouse) invest, or agree to invest in the future, at least $25,000 in certain funds in the Oppenheimer family of funds. More information about these and other discounts is available from your financial professional and in the section "About Your Account" beginning on page 10 of the prospectus and in the sections "How to Buy Shares" beginning on page 43 and "Appendix A" in the Fund's Statement of Additional Information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees (Oppenheimer Capital Appreciation Fund)	Class A	Class B	Class C	Class R	Class Y	Class I
Maximum Sales Charge (Load) imposed on purchases (as % of offering price)	5.75%	none	none	none	none	none
Maximum Deferred Sales Charge (Load) (as % of the lower of original offering price or redemption proceeds)	none	5.00%	1.00%	none	none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

^[1]

Annual Fund Operating Expenses (Oppenheimer Capital Appreciation Fund)	Class A	Class B	Class C	Class R	Class Y	Class I
Management Fees	0.59%	0.59%	0.59%	0.59%	0.59%	0.59%
Distribution and/or Service (12b-1) Fees	0.25%	1.00%	1.00%	0.50%	none	none
Other Expenses	0.23%	0.23%	0.23%	0.23%	0.23%	0.04%
Total Annual Fund Operating Expenses	1.07%	1.82%	1.82%	1.32%	0.82%	0.63%

Example. The following Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in a class of shares of the Fund for the time periods indicated. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your expenses would be as follows:

If shares are redeemed

Expense Example (Oppenheimer Capital Appreciation Fund) (USD $)	1 Year	3 Years	5 Years	10 Years
Class A	678	897	1,134	1,812
Class B	687	878	1,194	1,774
Class C	287	578	994	2,156
Class R	135	421	728	1,601
Class Y	84	263	457	1,018
Class I	65	202	352	789

If shares are not redeemed

Expense Example, No Redemption (Oppenheimer Capital Appreciation Fund) (USD $)	1 Year	3 Years	5 Years	10 Years
Class A	678	897	1,134	1,812
Class B	187	578	994	1,774
Class C	187	578	994	2,156
Class R	135	421	728	1,601
Class Y	84	263	457	1,018
Class I	65	202	352	789

Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in the annual fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 67% of the average value of its portfolio.

Principal Investment Strategies. The Fund mainly invests in common stocks of "growth companies." Growth companies are companies whose earnings and stock prices are expected to increase at a faster rate than the overall market. These may be newer companies or established companies of any capitalization range that the portfolio manager believes may appreciate in value over the long term. Currently, the Fund primarily focuses on established companies that are similar in size to companies in the S&P 500 Index or the Russell 1000 Growth Index. The Fund primarily invests in securities of U.S. issuers but may also invest in foreign securities. The portfolio manager looks for growth companies with stock prices that he believes are reasonable in relation to overall stock market valuations. In seeking broad diversification of the Fund's portfolio among industries and market sectors, the portfolio manager focuses on a number of factors that may vary in particular cases and over time. Currently, the portfolio manager looks for:

• companies in business areas that have above-average growth potential

• companies with growth rates that the portfolio manager believes are sustainable over time

• stocks with reasonable valuations relative to their growth potential.

The Fund may sell the stocks of companies that the portfolio manager believes no longer meet the above criteria, but is not required to do so.

Principal Risks. The price of the Fund's shares can go up and down substantially. The value of the Fund's investments may change because of broad changes in the markets in which the Fund invests or because of poor investment selection, which could cause the Fund to underperform other funds with similar investment objectives. There is no assurance that the Fund will achieve its investment objective. When you redeem your shares, they may be worth more or less than what you paid for them. These risks mean that you can lose money by investing in the Fund.

Risks of Investing in Stock. The value of the Fund's portfolio may be affected by changes in the stock markets. Stock markets may experience significant short-term volatility and may fall sharply at times. Different stock markets may behave differently from each other and U.S. stock markets may move in the opposite direction from one or more foreign stock markets.

The prices of individual stocks generally do not all move in the same direction at the same time and a variety of factors can affect the price of a particular company's stock. These factors may include, but are not limited to: poor earnings reports, a loss of customers, litigation against the company, general unfavorable performance of the company's sector or industry, or changes in government regulations affecting the company or its industry.

Industry and Sector Focus . At times the Fund may increase the relative emphasis of its investments in a particular industry or sector. The prices of stocks of issuers in a particular industry or sector may go up and down in response to changes in economic conditions, government regulations, availability of basic resources or supplies, or other events that affect that industry or sector more than others. To the extent that the Fund increases the relative emphasis of its investments in a particular industry or sector, its share values may fluctuate in response to events affecting that industry or sector. To some extent that risk may be limited by the Fund's policy of not concentrating its investments in any one industry.

Risks of Growth Investing. If a growth company's earnings or stock price fails to increase as anticipated, or if its business plans do not produce the expected results, its securities may decline sharply. Growth companies may be newer or smaller companies that may experience greater stock price fluctuations and risks of loss than larger, more established companies. Newer growth companies tend to retain a large part of their earnings for research, development or investments in capital assets. Therefore, they may not pay any dividends for some time. Growth investing has gone in and out of favor during past market cycles and is likely to continue to do so. During periods when growth investing is out of favor or when markets are unstable, it may be more difficult to sell growth company securities at an acceptable price. Growth stocks may also be more volatile than other securities because of investor speculation.

Who Is The Fund Designed For? The Fund is designed primarily for investors seeking capital appreciation over the long term. Those investors should be willing to assume the risks of short-term share price fluctuations that are typical for a fund focusing on stocks. Because of its focus on long-term growth, the Fund may be more appropriate for investors with longer term investment goals. The Fund is not designed for investors needing current income. The Fund is not a complete investment program. You should carefully consider your own investment goals and risk tolerance before investing in the Fund.

An investment in the Fund is not a deposit of any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

The Fund's Past Performance. The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance (for Class A shares) from calendar year to calendar year and by showing how the Fund's average annual returns for the periods of time shown in the table compare with those of a broad measure of market performance. The Fund's past investment performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. More recent performance information is available by calling the toll-free number on the back of this prospectus and on the Fund's website: https://www.oppenheimerfunds.com/fund/CapitalAppreciationFund

Sales charges and taxes are not included and the returns would be lower if they were. During the period shown, the highest return for a calendar quarter was 18.94% (2nd Qtr 09) and the lowest return was -28.10% (4th Qtr 08). For the period from January 1, 2014 to September 30, 2014 the cumulative return before sales charges and taxes was 9.47%.

The following table shows the average annual total returns for each class of the Fund's shares. After-tax returns are calculated using the highest individual federal marginal income tax rates and do not reflect the impact of state or local taxes. Your actual after-tax returns, depending on your individual tax situation, may differ from those shown and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns are shown for only one class and after-tax returns for other classes will vary.

Average Annual Total Returns for the periods ended December 31, 2013

Average Annual Total Returns (Oppenheimer Capital Appreciation Fund)		Inception Date	1 Year	5 Years (or life of class, if less)	10 Years (or life of class, if less)
Class A		Jan. 22, 1981	21.81%	16.39%	4.65%
Class A Return After Taxes on Distributions			20.57%	16.13%	4.48%
Class A Return After Taxes on Distributions and Sale of Fund Shares			13.30%	13.28%	3.70%
Class B		Nov. 01, 1995	23.23%	16.59%	4.76%
Class C		Dec. 01, 1993	27.25%	16.86%	4.46%
Class R		Mar. 01, 2001	27.90%	17.49%	4.96%
Class Y		Nov. 03, 1997	29.69%	18.25%	5.68%
Class I		Dec. 29, 2011	29.82%	21.54%
S&P 500 Index (reflects no deduction for fees, expenses or taxes)			32.39%	17.94%	7.41%
S&P 500 Index  (reflects no deduction for fees, expenses or taxes)	[1]			23.93%
Russell 1000 Growth Index (reflects no deduction for fees, expenses or taxes)			33.48%	20.39%	7.83%
Russell 1000 Growth Index  (reflects no deduction for fees, expenses or taxes)	[1]			24.04%

[1] As of 12/31/11.

[1] Expenses have been restated to reflect current fees.

XML

Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Document Type	dei_DocumentType	485BPOS
Document Period End Date	dei_DocumentPeriodEndDate	Aug. 31, 2014
Registrant Name	dei_EntityRegistrantName	OPPENHEIMER CAPITAL APPRECIATION FUND
Central Index Key	dei_EntityCentralIndexKey	0000319767
Amendment Flag	dei_AmendmentFlag	false
Document Creation Date	dei_DocumentCreationDate	Dec. 23, 2014
Document Effective Date	dei_DocumentEffectiveDate	Dec. 29, 2014
Prospectus Date	rr_ProspectusDate	Dec. 29, 2014