UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 11-K

x            Annual Report Pursuant To Section 15(d) of The Securities Exchange Act of 1934

For the fiscal year ended December 31, 2006

OR

o            Transition Report Pursuant To Section 15(d) of The Securities Exchange Act of 1934

For the transition period from                            to

Commission File Number 001-07935

A.    Full title of the plan and address of the plan, if different from that of the issuer named below:

INTERNATIONAL RECTIFIER CORPORATION
RETIREMENT SAVINGS PLAN

B.    Name of issuer of the securities held pursuant to the plan and the address of its principal executive office:

INTERNATIONAL RECTIFIER CORPORATION
233 KANSAS STREET
EL SEGUNDO, CALIFORNIA 90245

SIGNATURES

The Plan, pursuant to the requirements of the Securities Exchange Act of 1934, the trustees (or other persons who administer the employee benefit plan) have duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

	INTERNATIONAL RECTIFIER CORPORATION RETIREMENT SAVINGS PLAN
June 29, 2007	/s/ LINDA PAHL
	Linda Pahl
	Member of Administrative Committee

International Rectifier Corporation
Retirement Savings Plan
Index

Financial Statements

Supplemental Schedule

23.1 — Consent of Independent Registered Public Accounting Firm

Note:  All other schedules have been omitted since the information is either disclosed elsewhere in the financial statements or not required by 29 CFR 2520.103-10 of the Department of Labor Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974.

Report of Independent Registered Public Accounting Firm

To the Participants and Administrator of the
International Rectifier Corporation Retirement Savings Plan:

In our opinion, the accompanying statements of net assets available for benefits and the related statement of changes in net assets available for benefits present fairly, in all material respects, the net assets available for benefits of the International Rectifier Corporation Retirement Savings Plan (the “Plan”) at December 31, 2006 and 2005, and the changes in net assets available for benefits for the year ended December 31, 2006 in conformity with accounting principles generally accepted in the United States of America.  These financial statements are the responsibility of the Plan’s management.  Our responsibility is to express an opinion on these financial statements based on our audits.  We conducted our audits of these statements in accordance with the standards of the Public Company Accounting Oversight Board (United States).  Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement.  An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation.  We believe that our audits provide a reasonable basis for our opinion.

Our audits were conducted for the purpose of forming an opinion on the basic financial statements taken as a whole.  The supplemental Schedule of Assets (Held at End of Year) at December 31, 2006 is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974.  This supplemental schedule is the responsibility of the Plan’s management.  The supplemental schedule has been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole.

/s/ PRICEWATERHOUSECOOPERS, LLP

Los Angeles, California

June 22, 2007

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International Rectifier Corporation
Retirement Savings Plan
Statements of Net Assets Available for Benefits
December 31, 2006 and 2005

	2006		2005
Assets
Investments, at fair value	$	163,983,178	$	131,997,238
Net assets available for benefits, at fair value	163,983,178		131,997,238
Adjustment from fair value to contract value for fully benefit-responsive investment contracts	105,109		101,363
Net assets available for benefits	$	164,088,287	$	132,098,601

The accompanying notes are an integral part of these financial statements.

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International Rectifier Corporation
Retirement Savings Plan
Statement of Changes in Net Assets Available for Benefits
Year Ended December 31, 2006

Additions to net assets attributed to
Investment income
Interest and dividend income	$	6,152,175
Interest on participant loans	244,174
Net appreciation in the fair value of investments	12,134,946
	18,531,295
Contributions
Employee	13,358,871
Employer	10,187,946
	23,546,817
Total additions	42,078,112
Deductions from net assets attributed to
Benefits paid to participants	(10,069,691		)
Administrative fees	(18,735		)
Total deductions	(10,088,426		)
Net increase in net assets	31,989,686
Net assets available for benefits
Beginning of year	132,098,601
End of year	$	164,088,287

The accompanying notes are an integral part of these financial statements.

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International Rectifier Corporation
Retirement Savings Plan
Notes to Financial Statements
December 31, 2006 and 2005

1.             Description of the Plan

The following description of the International Rectifier Corporation Retirement Savings Plan (the “Plan”) provides only general information.  Participants should refer to the Plan agreement for a more complete description of the Plan’s provisions.

General

International Rectifier Corporation (the “Company” or “Plan Sponsor”) established the Plan on April 1, 1988.  The Plan is a defined contribution plan subject to the provisions of the Employee Retirement Income Security Act of 1974 (“ERISA”), as amended.

Eligibility

Effective June 1, 2002, an employee is eligible to participate in the Plan on the later of (i) the date on which the eligible employee’s employment commences, or (ii) the date on which he or she has attained age 18.

Contributions

Effective January 1, 2004, the Plan allowed participants to make up to 40% of their compensation in pre-tax contributions, including catch-up contributions for participants over age 50, subject to the Internal Revenue Code (the “code”) limits, and up to 40% of after-tax contributions, not to exceed $11,000.  Participants could also contribute amounts representing distributions from other qualified defined benefit or contribution plans.

The Company’s matching contribution is 150% of the first $200 of the participant’s contribution, plus 50% of the next $5,400, with the aggregate matching contribution made by the Company, not to exceed $3,000 per participant in a Plan year.  In addition to the Company’s matching contribution, the Board of Directors can make annual discretionary contributions in the form of cash or Company stock.  For the year ended December 31, 2006, there was a discretionary contribution authorized by the Board.

Vesting

Participants are immediately vested in their contributions and the Company’s matching and discretionary contributions plus actual earnings thereon.

Participant Accounts

Each participant’s account is credited with the participant’s contributions and allocations of the Company’s contribution and Plan earnings.  Allocations are based on participant contributions or account balances, as defined.  The benefit to which a participant is entitled is the benefit that can be provided from the participant’s vested account.

Investment Programs

The trustee for the Plan is Fidelity Management Trust Company (the “Trustee”).  All accounts are held in trust funds, Company unitized stock fund, or a self-directed brokerage account, which primarily consist of cash and cash equivalents, common stock and mutual funds.  All accounts are invested in accordance with the terms of the Plan and investment options elected by Plan participants.

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The self-directed brokerage account was offered to Plan participants beginning in 2000 and enables Plan participants to purchase or sell individual securities within their accounts.  The Plan document defines the eligible securities the participants can invest in within the self-directed brokerage account.  The purchase and sale of Company stock is not permitted as an investment option for participants who use the brokerage link account. The custodian of the Plan is Fidelity Brokerage Service, Inc. (“Fidelity Brokerage”).  Fidelity Brokerage executes the investment transactions, collects interest and dividend income and retains custody of the investment securities within the guidelines of ERISA.

Participants can allocate their contributions and account balances to any or all of the investment fund options and the self-directed brokerage account.  Participants may transfer their account balances, or a portion thereof, from one fund to another, or from a fund to the self-directed brokerage account.  However, all assets transferred from the self-directed brokerage account are first credited to a default fund designated by the Plan.  The participants may then transfer their account balances to other funds.  Participants may not make direct transfers from the Managed Income Portfolio into the self-directed brokerage account.

Profit Sharing

From fiscal year 2006, the Company implemented a process by which the company might make profit sharing contributions (“PSC”) designed to ensure that all eligible employees continue to be rewarded for their contributions and share in the success of the Company.  This PSC modifies the provisions of Section 3.4 of the Plan regarding Discretionary Employer Contributions.

Each fiscal year, the Compensation Committee of the Board of Directors will determine the amount of the overall Discretionary Employer Contribution, if any, in its sole discretion.  For U.S. employees, the payout is made directly to the Plan on a salary based allocation to each eligible employee.  During 2006, the PSC payout to the Plan amounted to $6,486,345.

Participant Loans

The Plan allows participants to borrow from their accounts a minimum of $1,000 up to a maximum equal to the lesser of 50% of their vested account balance or $50,000 less the highest outstanding loan balance from the Plan during the prior twelve months.  Loan terms range from one to five years or up to ten years for the purchase of a primary residence.  The loans are collateralized by the balance in the participant’s account and bear interest at a rate commensurate with comparable prevailing rates as determined periodically.  Principal and interest are paid ratably through bi-weekly payroll deductions.

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Benefit Payments

A participant who is currently in service may withdraw all or a portion of his or her vested accounts after attainment of age 59 1/2.  A participant is limited to two withdrawals under this option during any twelve-month period.  Upon termination of service, a participant will receive a lump-sum amount equal to the value of the participant’s account, as defined by the Plan, unless the participant chooses to leave the account balance in the Plan.  A former employee participant may leave his or her account balance in the Plan if the balance exceeds $5,000 and the participant has not yet attained normal retirement age, while a currently employed participant may leave his or her account balance in the Plan as long as they remain a currently employed participant.  Benefits are recorded when paid.

Effective March 28, 2005, if the Participant’s distributable benefit is greater than $1,000 but equal to or less than $5,000, if the Participant does not affirmatively elect to have such benefit either (1) paid directly to an eligible retirement plan specified by the Participant in a direct rollover, or (2) paid to the Participant directly, then the Plan shall pay the distribution in a direct rollover to an individual retirement plan designated by the Plan.

2.             Summary of Accounting Policies

Basis of Accounting

The accompanying financial statements of the Plan are prepared using the accrual method of accounting and in accordance with the accounting principles generally accepted in the United States of America.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts in the statement of changes in net assets available for benefits during the reporting period.  Actual results could differ from those estimates.

Risks and Uncertainties

The Plan provides for various investment options in mutual funds, common stock and other securities.  Investment securities are exposed to various risks, such as interest rate, market and credit.  Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in risks in the near term would materially affect participants’ account balances and the amounts reported in the statement of net assets available for benefits and the statement of changes in net assets available for benefits.

Investments

The Plan’s investments are stated at fair value.  The Plan’s investments in shares of common stock are valued at the last quoted sales price on the last business day of the year.  Shares in registered investment companies are valued at the net asset value of shares held by the Plan at year end.

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The commingled trust fund is presented at fair value.  This investment, which is a fully responsive benefit contract, is also stated at contract value which is equal to principal balance plus accrued interest.  Such investment contract is generally valued at contract value, rather than fair value, to the extent it is fully benefit-responsive.  The fair value of the fully benefit-responsive investment contracts is calculated using a discounted cash flow model which considers recent fee bids as determined by recognized dealers, discount rate and the duration of the underlying portfolio securities.

Participant loans are valued at the unpaid amount of the loan that is estimated to approximate fair value.

Purchases and sales of securities are reflected on a trade date basis.  The basis for all securities sold is determined by average cost.  Dividend income is recorded on the ex-dividend date and interest income is recorded on the accrual basis.  The Plan presents in the statement of changes in net assets available for benefits the net appreciation (depreciation) in fair value of its investments, which consists of the realized gains or losses and unrealized appreciation or depreciation on those investments.

3.             Investments

The following are investments that represent 5% or more of the Plan’s net assets at December 31:

	2006		2005
International Rectifier Unitized Stock Fund	$	21,027,233	$	20,332,025
Fidelity Growth Company Fund	22,543,986		19,901,034
Fidelity Value Fund	22,485,225		19,250,767
Fidelity Retirement Government Money Market Portfolio	15,755,529		11,531,491
Fidelity Diversified International Fund	13,045,312		7,039,383
Fidelity Low-Priced Stock Fund	11,694,046		9,439,521
Fidelity Managed Income Portfolio	10,524,630		9,196,363
Fidelity Intermediate Bond Fund	9,758,621		8,073,532

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For the year ended December 31, 2006, the Plan’s investments (including gains and losses on investments bought and sold, as well as held during the year) appreciated in value by $12,134,946 as follows:

Mutual funds	$	6,914,147
Company common stock	5,155,654
Self-directed brokerage account — Other	65,145
	$	12,134,946

4.             Related-Party Transactions

Certain of the Plan’s investments are shares of mutual funds managed by the trustee of the Plan.  In addition, Fidelity Brokerage, the custodian of the Plan, executes the investment transactions within the self-directed brokerage account.  Therefore, these transactions qualify as party-in-interest transactions for which a statutory exemption exists.  Fees paid by the Plan for investment management services were nominal for the year ended December 31, 2006.

The Company also qualifies as a party-in-interest and absorbs certain administrative expenses of the Plan.  The Company paid $47,824 of administrative expenses on behalf of the Plan for the year ended December 31, 2006.  Such transactions with the Company qualify for a statutory exemption.  Participant loans are considered party-in-interest transactions, and thus qualify for statutory exemption.

The Plan also offers the International Rectifier Unitized Stock Fund investment option. The International Rectifier Unitized Stock Fund is designed primarily for investment in common stock of the Company.  Transactions in this investment qualify as exempt party-in-interest transactions.

During the year ended December 31, 2006, the cost of purchasing International Rectifier common stock was $7,981,688 and sales proceeds were $12,149,156.

5.             Plan Termination

Although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA.  Upon a partial or complete termination of the Plan, the account balances of the participants are non-forfeitable and will be determined as of the termination date.

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6.             Tax Status of the Plan

The Plan has obtained a favorable tax determination letter from the Internal Revenue Service dated April 30, 2002.  The Plan has been amended since receiving the determination letter.  However, the Plan administrator and the Plan’s tax counsel believe that the Plan is designed and is currently in compliance with the applicable requirements of the code.  Therefore, the Company believes that the Plan qualified as tax-exempt for the year ended December 31, 2006.

7.             New Accounting Pronouncements

As of December 31, 2006, the Plan adopted Financial Accounting Standards Board (FASB) Staff Position, FSP AAG INV-1 and Statement of Position No. 94-4-1, Reporting of Fully Benefit-Responsive Investment Contracts Held by Certain Investment Companies Subject to the AICPA Investment Company Guide and Defined-Contribution Health and Welfare and Pension Plans (the FSP). The FSP requires the Statement of Net Assets Available for Benefits to present the fair value of the Plan’s investments as well as the adjustment from fair value to contract value for the fully benefit-responsive investment contracts.  As required by the FSP, the Statement of Changes in Net Assets Available for Benefits is prepared on a contract value basis for the fully benefit-responsive investment contracts.  The FSP was applied retroactively to the prior period presented on the Statement of Net Assets Available for Benefit.

In September 2006, the FASB issued SFAS No. 157, “Fair Value Measurements” (“SFAS No. 157”).  This Statement defines fair value, establishes a framework for measuring fair value and expands disclosures regarding fair value measurements.  SFAS No. 157 will be effective beginning in the first quarter of fiscal year 2009 ending September 30, 2008.  The Company is currently evaluating the impact of SFAS No. 157.

On September 13, 2006, the Securities and Exchange Commission (SEC) issued Staff Accounting Bulletin (SAB) No. 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements, which provides interpretive guidance on the consideration of the effects of prior year misstatements in quantifying current year misstatements for the purpose of a materiality assessment. SAB No. 108 is effective for fiscal years ending after November 14, 2006, or for the Plan calendar year ending December 31, 2006. The adoption of SAB No. 108 did not have any impact on the Plan’s net assets available for benefits and changes in net assets available for benefits.

8.             Subsequent Events

The Plan Sponsor directed the Trustee, effective at the close of business April 27, 2007, to close the International Rectifier Unitized Stock Fund to new participant contributions, loan repayment and exchanges in, and to redirect all participant contributions directed to the International Rectifier Unitized Stock Fund to be invested in a Fidelity Freedom Fund.

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9.             Reconciliation of Financial Statements to Form 5500

The following is a reconciliation of investment income per the financial statements to the Form 5500:

Total Investment Income per Financial Statements	$	31,989,686
Less: Adjustment from fair value for fully benefit responsive investment contracts	(105,109		)
Total Investment Income per Form 5500	$	31,884,577

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Supplemental Schedule

International Rectifier Corporation
Retirement Savings Plan
EIN 95-1528961  PN 003
Schedule H, line 4i- Schedule of Assets (Held at End of Year **)
December 31, 2006

(a)	(b) Identity of Issue, Borrower, Lessor or Similar Party	(c) Description of Investment, Including Maturity Date, Rate of Interest, Collateral, Par or Maturity Value	(e) Current Value
*	Fidelity Growth Company Fund	Shares in Registered Investment Company	$	22,543,986
*	Fidelity Value Fund	Shares in Registered Investment Company	22,485,226
*	International Rectifier Unitized Stock Fund	Company Stock	21,027,233
*	Fidelity Retirement Government Money Market Portfolio	Shares in Registered Investment Company	15,755,530
*	Fidelity Diversified International Fund	Shares in Registered Investment Company	13,045,312
*	Fidelity Low-Priced Stock Fund	Shares in Registered Investment Company	11,694,046
*	Fidelity Managed Income Portfolio	Shares in Commingled Trust Fund	10,524,630
*	Fidelity Intermediate Bond Fund	Shares in Registered Investment Company	9,758,621
*	Spartan U.S. Equity Index Fund	Shares in Registered Investment Company	7,192,788
*	Fidelity Equity Income	Shares in Registered Investment Company	4,977,460
*	Fidelity Blue Chip Growth Fund	Shares in Registered Investment Company	4,705,263
*	Fidelity Freedom 2020	Shares in Registered Investment Company	2,758,152
*	Fidelity Fund	Shares in Registered Investment Company	2,034,794
*	Fidelity Freedom 2030	Shares in Registered Investment Company	1,999,756
*	Fidelity Small Cap Stock Fund	Shares in Registered Investment Company	1,808,867
*	Fidelity Freedom 2010	Shares in Registered Investment Company	1,793,086
*	Fidelity Freedom 2040	Shares in Registered Investment Company	855,506
*	Fidelity Freedom 2000	Shares in Registered Investment Company	482,937
*	Fidelity Freedom Income	Shares in Registered Investment Company	434,926
	Brokeragelink	Self-Directed Brokerage Account	4,422,798
*	Participant loans	Interest rates range from 6.50% to 9.25% and maturing between January 2006 and October 2015	3,682,261
			$	163,983,178

*        A party-in-interest for which a statutory exemption exists.

**Under ERISA, an asset held for investment purposes is any asset held by the Plan on the last day of the Plan year and any investment asset purchased during the Plan year sold before the end of the Plan year, with certain exceptions.

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International Rectifier Corporation
Retirement Savings Plan
Exhibit Index

Exhibit	Description
23.1	Consent of PricewaterhouseCoopers LLP

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