Exhibit 99.1

FOR IMMEDIATE RELEASE

Editor’s Contact:
Steve Sturgeon
QLogic Corporation
Phone: (949) 389-6268
steve.sturgeon@qlogic.com

Investor’s Contact:
Michael Roe
QLogic Corporation
Phone: (949) 389-6440
michael.roe@qlogic.com

QLOGIC REPORTS FOURTH QUARTER
AND FISCAL YEAR 2004 RESULTS

Aliso Viejo, Calif., April 28, 2004 – QLogic Corporation (Nasdaq:QLGC), the company that powers storage area networks (SANs), today announced its financial results for the fourth quarter and fiscal year ended March 28, 2004. These results are consistent with the preliminary results previously announced on March 30, 2004.

Net revenues for the fourth quarter of fiscal 2004 were $128.3 million and increased 6% from the $120.6 million reported in the comparable quarter last year. Fibre Channel revenues for the fourth quarter of fiscal 2004 were $103.0 million and represented 80% of the Company’s total revenue. Fibre Channel revenues for the fourth quarter were up 20% from the comparable quarter last year. Net income on a GAAP basis for the fourth quarter of fiscal 2004 was $32.9 million, or $0.34 per share on a diluted basis and increased 10% from the $29.9 million, or $0.31 per share on a diluted basis, reported in the fourth quarter of last year.

During the fourth quarter of fiscal 2004, net revenues decreased sequentially from the $137.1 million reported in the third quarter of fiscal 2004. Fourth quarter net income on a GAAP basis decreased sequentially from the $35.0 million, or $0.36 per share on a diluted basis, reported in the third quarter of fiscal 2004.

Net revenues for fiscal 2004 were $523.9 million, up 19% from the $440.8 million reported in fiscal year 2003. Net income on a GAAP basis for fiscal 2004 was $133.7 million, or $1.39 per share on a diluted basis. This fiscal year 2004 net income increased 29% from the $103.5 million, or $1.09 per share on a diluted basis reported last year.

The Company uses certain non-GAAP measures to supplement financial statements based on GAAP. These non-GAAP measures include adjustments for merger related stock compensation charges, legal settlements, and in fiscal 2003, sales discounts for stock warrants and an impairment of an investment in a technology company. A description of the purpose and benefit of such non-GAAP financial information is presented below and a reconciliation between the GAAP and non-GAAP measures is included in the accompanying financial data.

Non-GAAP net income for the fourth quarter of fiscal 2004 was $34.7 million, or $0.36 per share on a diluted basis and increased 9% from the $32.0 million, or $0.33 per share on a diluted basis, reported in the fourth quarter of last year. Non-GAAP net income for the fourth quarter of fiscal 2004 declined sequentially from the $37.9 million, or $0.39 per share on a diluted basis reported for the third quarter of fiscal 2004.

During fiscal 2004, the Company’s non-GAAP net income was $142.5 million, or $1.48 per share on a diluted basis. This fiscal year 2004 net income increased 25% from the $114.4 million, or $1.20 per share on a diluted basis, reported last year.

“During fiscal 2004, QLogic achieved a number of milestones, including the establishment of new records for annual revenue and net income. On a GAAP basis, net revenues for fiscal 2004 increased 19% to $524 million and net income increased 29% to $134 million from the prior fiscal year,” said H.K. Desai, the Company’s chairman, chief executive officer and president. “Our overall performance during the fiscal year demonstrated strong revenue growth and profitability. With our current year design wins, we are well positioned for continued growth in fiscal 2005.”

The Company’s balance sheet was again highlighted by an increase in cash and short-term investments, ending the quarter with $743 million. During fiscal 2004, cash and short-term investments increased by $100 million, net of the $57 million the Company used to purchase its common stock pursuant to the previously authorized stock repurchase program. During April 2004, the Company purchased an additional $20 million of its common stock under the stock repurchase program.

QLogic’s fourth quarter and fiscal year 2004 conference call is scheduled today at 2:30 p.m. Pacific Time (5:30 p.m. Eastern Time). H.K. Desai, chairman of the board, chief executive officer and president, and Frank Calderoni, senior vice president and chief financial officer, will host the conference call. The call is being webcast live via the Internet at www.qlogic.com or via CCBN. Phone access to participate in the conference call is available at (913) 981-4901, passcode: 750734.

The quarterly and fiscal year financial information that the Company intends to discuss during the conference call is included in this press release and will be available on the Company’s website at www.qlogic.com for 12 months following the conference call. To listen to a webcast replay of the conference call, please visit the Investor Relations section of the Company’s website at www.qlogic.com. The webcast replay will be available for 12 months following the conference call. An audio replay of the conference call will also be available through May 12, 2004 by calling (719) 457-0820, passcode: 750734.

Non-GAAP Financial Measurements

The non-GAAP net income and related net income per share amounts supplement the corresponding financial measurements computed in accordance with generally accepted accounting principles (GAAP) and excludes non-cash merger related stock compensation charges, legal settlements, sales discounts for stock warrants and an impairment of an investment in a technology company. The Company has provided these non-GAAP financial measures to assist investors to better understand the Company’s core operating performance and to enhance comparisons of its core operating performance with historical periods and the operating performance of its competitors. Items excluded from non-GAAP financial measurements are also excluded by management in its evaluation of the core operating performance of the Company and in its evaluation of trends between fiscal periods. In addition, the Company prepares and maintains all budgets and forecasts of future periods on a basis consistent with these non-GAAP financial measurements. Investors should consider non-GAAP measures in addition to, and not as a substitute for, or as superior to, measures of financial performance prepared in accordance with GAAP.

Powered by QLogic

Since 1993, over 50 million QLogic products have shipped inside servers, workstations, RAID subsystems, tape libraries, disk and tape drives. These products were delivered to small, medium and large enterprises around the world. Powering solutions from leading companies like Cisco, Dell, EMC, Fujitsu, Hitachi, HP, IBM, Network Appliance, Quantum, StorageTek and Sun Microsystems, the broad line of QLogic controller chips, host bus adapters, network switches and management software move data from storage devices through the network fabric to servers. A member of the S&P 500 and NASDAQ 100, QLogic was named to the following during fiscal year 2004: (i) Fortune’s 100 Fastest Growing Companies list for the fourth consecutive year; (ii) Forbes’ Best 200 Small Companies for the fifth consecutive year; and (iii) Business Week’s list of 100 Hot Growth Companies. For more information visit www.qlogic.com.

Note: All QLogic-issued press releases appear on the Company’s website (www.qlogic.com). Any announcement that does not appear on the QLogic website has not been issued by QLogic.

Disclaimer — Forward Looking Statements

This press release contains statements relating to future results of the Company (including certain beliefs and projections regarding business trends) that are “forward-looking statements” as defined within the Private Securities Litigation Reform Act of 1995. Such forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially from those projected or implied in the forward-looking statements. The Company wishes to advise readers that these potential risks and

uncertainties include, but are not limited to: the volatility of the Company’s stock price; fluctuations in operating results; the dependence on the storage area network market; the ability to maintain and gain market or industry acceptance of the Company’s products; the dependence on a limited number of customers and fluctuations or cancellations in orders from customers; the ability to compete effectively with other companies; a reduction in sales efforts by current distributors; the dependence on relationships with certain silicon chip suppliers and other subcontractors; the complexity of the Company’s products; terrorist activities and resulting military actions; international, economic, regulatory, political and other risks; changes in semiconductor foundry capacity; the ability to maintain or expand upon strategic alliances; the strain on resources caused by rapid growth and expansion; the ability to attract and retain key personnel; and the ability to protect proprietary rights or to satisfactorily resolve any infringement claims.

More detailed information on these and additional factors which could affect the Company’s operating and financial results are described in the Company’s Forms 10-K, 10-Q and other reports, filed or to be filed with the Securities and Exchange Commission. The Company urges all interested parties to read these reports to gain a better understanding of the many business and other risks that the Company faces. The forward looking statements contained in this press release are made only as of the date hereof, and the Company undertakes no obligation to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise.

Trademarks and registered trademarks are the property of the companies with which they are associated.

QLOGIC CORPORATION

SUMMARY CONSOLIDATED RESULTS OF OPERATIONS

(unaudited — in thousands, except per share amounts)

Consolidated GAAP Results

	Three Months Ended						Years Ended
	Mar. 28,		Dec. 28,		Mar. 30,		Mar. 28,		Mar. 30,
	2004		2003		2003		2004		2003
Net revenues	$	128,294	$	137,064	$	120,565	$	523,860	$	440,809
Gross profit		89,249		94,183		79,410		357,566		281,439
Operating income		48,625		52,879		42,569		198,757		141,863
Net income		32,864		34,952		29,889		133,673		103,473
Net income per share — diluted		0.34		0.36		0.31		1.39		1.09
Weighted average common shares outstanding — diluted		95,798		96,823		95,444		96,246		95,354

Consolidated Results Excluding Non-GAAP Adjustments

	Three Months Ended						Years Ended
	Mar. 28,		Dec. 28,		Mar. 30,		Mar. 28,		Mar. 30,
	2004		2003		2003		2004		2003
Net revenues	$	128,294	$	137,064	$	120,565	$	523,860	$	444,037
Gross profit		89,249		94,183		79,410		357,566		284,667
Operating income		50,494		56,499		44,640		208,250		151,864
Net income		34,733		37,888		31,960		142,482		114,416
Net income per share — diluted		0.36		0.39		0.33		1.48		1.20
Weighted average common shares outstanding — diluted		95,798		96,823		95,444		96,246		95,354

QLOGIC CORPORATION

SUMMARY CONSOLIDATED RESULTS OF OPERATIONS (continued)

(unaudited — in thousands)

Description of Non-GAAP Adjustments

A summary of the non-GAAP adjustments reported by QLogic is as follows:

	Three Months Ended							Years Ended
	Mar. 28,		Dec. 28,			Mar. 30,		Mar. 28,			Mar. 30,
	2004		2003			2003		2004			2003
Merger related stock compensation charges	$	1,869	$	1,870		$	2,071	$	7,743		$	6,773
Legal settlements		—		1,750			—		1,750			—
Sales discounts for stock warrants		—		—			—		—			3,228
Technology company investment impairment		—		—			—		—			3,000
Pre-tax adjustments		1,869		3,620			2,071		9,493			13,001
Income tax effect		—		(684	)		—		(684	)		(2,058	)
After-tax non-GAAP adjustments	$	1,869	$	2,936		$	2,071	$	8,809		$	10,943

Non-GAAP Financial Measurements

In addition to the results presented throughout this document in accordance with generally accepted accounting principles (GAAP), the Company has provided non-GAAP measurements, which present operating results on a basis excluding certain non-GAAP adjustments. Details of these adjustments are presented in the table above.

The Company has provided these non-GAAP financial measures to assist investors to better understand the Company’s core operating performance and to enhance comparisons of its core operating performance with historical periods and the operating performance of its competitors. Management uses the non-GAAP operating results in its evaluation of the core operating performance of the Company and in its evaluation of trends between fiscal periods. In addition, the Company prepares and maintains all budgets and forecasts of future periods on a basis consistent with these non-GAAP operating results. Investors should consider non-GAAP measures in addition to, and not as a substitute for, or as superior to, measures of financial performance prepared in accordance with GAAP.

QLOGIC CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited — in thousands, except per share amounts)

	Three Months Ended March 28, 2004							Three Months Ended March 30, 2003
	GAAP		Non-GAAP			Non-GAAP		GAAP		Non-GAAP			Non-GAAP
	Results		Adjustments			Results		Results		Adjustments			Results
Gross revenues	$	128,294	$	—		$	128,294	$	120,565	$	—		$	120,565
Stock-based sales discounts		—		—			—		—		—			—
Net revenues		128,294		—			128,294		120,565		—			120,565
Cost of revenues		39,045		—			39,045		41,155		—			41,155
Gross profit		89,249		—			89,249		79,410		—			79,410
Operating expenses:
Engineering and development		22,024		(1,869	)		20,155		21,901		(2,071	)		19,830
Sales and marketing		14,941		—			14,941		11,304		—			11,304
General and administrative		3,659		—			3,659		3,636		—			3,636
Total operating expenses		40,624		(1,869	)		38,755		36,841		(2,071	)		34,770
Operating income		48,625		1,869			50,494		42,569		2,071			44,640
Interest and other income		4,381		—			4,381		5,160		—			5,160
Income before income taxes		53,006		1,869			54,875		47,729		2,071			49,800
Income taxes		20,142		—			20,142		17,840		—			17,840
Net income	$	32,864	$	1,869		$	34,733	$	29,889	$	2,071		$	31,960
Net income per share:
Basic	$	0.35	$	0.02		$	0.37	$	0.32	$	0.02		$	0.34
Diluted	$	0.34	$	0.02		$	0.36	$	0.31	$	0.02		$	0.33
Number of shares used in per share computations:
Basic		94,367		—			94,367		93,771		—			93,771
Diluted		95,798		—			95,798		95,444		—			95,444

QLOGIC CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited — in thousands, except per share amounts)

	Three Months Ended March 28, 2004							Three Months Ended December 28, 2003
	GAAP		Non-GAAP			Non-GAAP		GAAP		Non-GAAP			Non-GAAP
	Results		Adjustments			Results		Results		Adjustments			Results
Gross revenues	$	128,294	$	—		$	128,294	$	137,064	$	—		$	137,064
Stock-based sales discounts		—		—			—		—		—			—
Net revenues		128,294		—			128,294		137,064		—			137,064
Cost of revenues		39,045		—			39,045		42,881		—			42,881
Gross profit		89,249		—			89,249		94,183		—			94,183
Operating expenses:
Engineering and development		22,024		(1,869	)		20,155		21,514		(1,870	)		19,644
Sales and marketing		14,941		—			14,941		13,846		—			13,846
General and administrative		3,659		—			3,659		5,944		(1,750	)		4,194
Total operating expenses		40,624		(1,869	)		38,755		41,304		(3,620	)		37,684
Operating income		48,625		1,869			50,494		52,879		3,620			56,499
Interest and other income		4,381		—			4,381		3,495		—			3,495
Income before income taxes		53,006		1,869			54,875		56,374		3,620			59,994
Income taxes		20,142		—			20,142		21,422		684			22,106
Net income	$	32,864	$	1,869		$	34,733	$	34,952	$	2,936		$	37,888
Net income per share:
Basic	$	0.35	$	0.02		$	0.37	$	0.37	$	0.03		$	0.40
Diluted	$	0.34	$	0.02		$	0.36	$	0.36	$	0.03		$	0.39
Number of shares used in per share computations:
Basic		94,367		—			94,367		94,458		—			94,458
Diluted		95,798		—			95,798		96,823		—			96,823

QLOGIC CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited — in thousands, except per share amounts)

	Year Ended March 28, 2004							Year Ended March 30, 2003
	GAAP		Non-GAAP			Non-GAAP				Non-GAAP			Non-GAAP
	Results		Adjustments			Results		GAAP Results		Adjustments			Results
Gross revenues	$	523,860	$	—		$	523,860	$	444,037	$	—		$	444,037
Stock-based sales discounts		—		—			—		3,228		(3,228	)		—
Net revenues		523,860		—			523,860		440,809		3,228			444,037
Cost of revenues		166,294		—			166,294		159,370		—			159,370
Gross profit		357,566		—			357,566		281,439		3,228			284,667
Operating expenses:
Engineering and development		87,755		(7,743	)		80,012		81,253		(6,773	)		74,480
Sales and marketing		52,952		—			52,952		44,312		—			44,312
General and administrative		18,102		(1,750	)		16,352		14,011		—			14,011
Total operating expenses		158,809		(9,493	)		149,316		139,576		(6,773	)		132,803
Operating income		198,757		9,493			208,250		141,863		10,001			151,864
Interest and other income		16,844		—			16,844		17,356		3,000			20,356
Income before income taxes		215,601		9,493			225,094		159,219		13,001			172,220
Income taxes		81,928		684			82,612		55,746		2,058			57,804
Net income	$	133,673	$	8,809		$	142,482	$	103,473	$	10,943		$	114,416
Net income per share:
Basic	$	1.42	$	0.09		$	1.51	$	1.11	$	0.11		$	1.22
Diluted	$	1.39	$	0.09		$	1.48	$	1.09	$	0.11		$	1.20
Number of shares used in per share computations:
Basic		94,281		—			94,281		93,469		—			93,469
Diluted		96,246		—			96,246		95,354		—			95,354

QLOGIC CORPORATION

CONDENSED CONSOLIDATED BALANCE SHEETS

(unaudited — in thousands)

	Mar. 28, 2004		Mar. 30, 2003
ASSETS
Current assets:
Cash and cash equivalents	$	156,593	$	137,810
Short-term investments		586,441		505,387
Accounts receivable, net		67,355		49,694
Inventories		20,935		19,365
Other current assets		22,256		35,924
Total current assets		853,580		748,180
Property and equipment, net		67,224		59,813
Other assets		7,711		9,426
	$	928,515	$	817,419
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Accounts payable	$	18,570	$	15,301
Accrued compensation		18,849		21,997
Income taxes payable		10,691		19,201
Other liabilities		12,687		10,185
Total current liabilities		60,797		66,684
Total stockholders’ equity		867,718		750,735
	$	928,515	$	817,419

QLOGIC CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(unaudited — in thousands)

	Years Ended
	Mar. 28,			Mar. 30,
	2004			2003
Cash flows from operating activities:
Net income	$	133,673		$	103,473
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization		14,829			14,706
Deferred income taxes		15,420			5,937
Tax benefit from issuance of stock under stock plans		10,640			6,037
Amortization of deferred stock-based compensation		1,196			1,904
Provision for losses on accounts receivable		(450	)		(550	)
Loss on disposal of property and equipment		43			1,478
Write-down of non-marketable investments		—			4,000
Stock-based sales discounts		—			3,228
Changes in operating assets and liabilities:
Accounts receivable		(17,211	)		(10,784	)
Inventories		(1,570	)		5,393
Other assets		(37	)		(1,229	)
Accounts payable		3,269			276
Accrued compensation		(3,148	)		6,855
Income taxes payable		(8,510	)		10,606
Other liabilities		9,048			3,974
Net cash provided by operating activities		157,192			155,304
Cash flows from investing activities:
Purchases of marketable securities		(974,494	)		(858,202	)
Sales and maturities of marketable securities		893,122			773,338
Additions to property and equipment		(22,283	)		(15,704	)
Acquisition of business		—			(1,695	)
Net cash used in investing activities		(103,655	)		(102,263	)
Cash flows from financing activities:
Proceeds from issuance of stock under stock plans		22,260			11,623
Purchase of treasury stock		(57,014	)		(2,978	)
Net cash provided by (used in) financing activities		(34,754	)		8,645
Net increase in cash and cash equivalents		18,783			61,686
Cash and cash equivalents at beginning of period		137,810			76,124
Cash and cash equivalents at end of period	$	156,593		$	137,810