<PAGE>   1

   As Filed With the Securities and Exchange Commission on October 30, 1998.
                                                Registration No. 333-___________

================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON. D.C. 20549

                                   ----------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                                   ----------

                               QLOGIC CORPORATION
             (Exact name of registrant as specified in its charter)

           DELAWARE                                      33-0537669
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
 incorporation or organization)


               3545 HARBOR BOULEVARD, COSTA MESA, CALIFORNIA 92626
               (Address of Principal Executive Offices) (Zip Code)

                                   ----------

                          EMPLOYEE STOCK PURCHASE PLAN
                                STOCK AWARDS PLAN
                           (Full titles of the plans)

                                   ----------

         Thomas R. Anderson, Vice President and Chief Financial Officer
                               QLogic Corporation
                              3545 Harbor Boulevard
                          Costa Mesa, California 92626
                     (Name and address of agent for service)

                                 (714) 438-2200
          (Telephone number, including area code, of agent for service)

                                    Copy to:
                               Nick E. Yocca, Esq.
           Stradling Yocca Carlson & Rauth, a Professional Corporation
      660 Newport Center Drive, Suite 1600, Newport Beach, California 92660
                                 (949) 725-4000

                         CALCULATION OF REGISTRATION FEE

<TABLE>
<CAPTION>
===============================================================================================
                                        Proposed Maximum   Proposed Maximum 
Title of Securities    Amount To Be      Offering Price        Aggregate         Amount of
 To Be Registered      Registered(1)       Per Share        Offering Price    Registration Fee
===============================================================================================
<S>                   <C>                  <C>             <C>                   <C>       
  Common Stock,
  $0.10 par value     675,000 shares       $86.625(2)      $58,471,875.00(2)     $16,256.00
===============================================================================================
</TABLE>

     (1) Includes additional shares of Common Stock that may become issuable
     pursuant to the anti-dilution adjustment provisions of the Employee Stock
     Purchase Plan (the "Purchase Plan") and the Stock Awards Plan (the "Awards
     Plan").

     (2) In accordance with Rule 457(h), the aggregate offering price of 300,000
     shares of Common Stock registered hereby which the Registrant is authorized
     to issue under the Purchase Plan and of the additional 375,000 shares which
     the Registrant is authorized to issue under the Awards Plan is estimated
     solely for purposes of calculating the registration fee on the basis of the
     price of securities of the same class, as determined in accordance with
     Rule 457(c), using the average of the high and low price reported by the
     Nasdaq National Market for the Common Stock on October 26, 1998, which was
     $86.625 per share.

PAGE 1 OF ___ PAGES                                   EXHIBIT INDEX ON PAGE [__]

<PAGE>   2

PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

        This registration statement relates to both the Stock Awards Plan, as
amended ("Awards Plan"), of the Registrant and the Employee Stock Purchase Plan
("ESPP") of the Registrant. An aggregate of 1,350,000 shares of the Registrant's
common stock issuable pursuant to the Awards Plan have previously been
registered on Form S-8, Registration No. 33-75814, filed February 28, 1994, and
Form S-8, Registration No. 333-13137, filed October 1, 1996, and the contents of
both such registration statements are incorporated by reference except as
revised herein. On August 1, 1997, the Registrant's Board of Directors amended
the Awards Plan to further increase the number of shares issuable thereunder by
375,000, from 1,350,000 shares to 1,725,000 shares, and on August 11, 1997,
amended the Awards Plan to establish 500,000 shares as the maximum number of
derivative securities and shares of common stock that may be granted to any one
participant in any calendar year. Both such amendments were adopted subject to
stockholder approval, which was obtained at the Registrant's Annual Meeting of
Stockholders held on September 23, 1997. Pursuant to General Instruction E of
Form S-8, this registration statement registers the additional 375,000 shares
issuable under the Awards Plan.

Item 3.  Incorporation of Documents by Reference.

        The following documents are incorporated herein by reference:

        (a) The contents of the Registrant's Registration Statement on Form S-8
(Registration No. 33-75814) as filed with the Securities and Exchange Commission
(the "Commission") on February 28, 1994;

        (b) The contents of the Registrant's Registration Statement on Form S-8
(Registration No. 333-13137) as filed with the Commission on October 1, 1996;

        (c) The Registrant's Annual Report on Form 10-K for its fiscal year
ended March 29, 1998, filed with the Commission under the Securities Exchange
Act of 1934, as amended (the "Exchange Act") on June 17, 1998;

        (d) The Registrant's Quarterly Report on Form 10-Q for its fiscal
quarter ended June 28, 1998, filed with the Commission under the Exchange Act on
August 11, 1998;

        (e) All other reports filed by the Registrant pursuant to Section 13(a)
or 15(d) of the Exchange Act since the end of the fiscal year covered by the
report referred to in (c) above;

        (f) The description of the Registrant's Common Stock that is contained
in the Registrant's Registration Statement on Form 10 (Commission file number
0-23298) filed with the Commission under the Exchange Act on February 15, 1994;

        (g) The description of the Rights to Purchase Series A Junior
Participating Preferred Stock (the "Rights") and of the Series A Junior
Participating Preferred Stock, par value $0.001 per share, that is contained in
the Registrant's Registration Statement on Form 8-A filed with the Commission
under Section 12 of the Exchange Act on June 19, 1996, including any amendment
or report filed for the purpose of updating that description.

        All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a
post-effective amendment which indicates that all securities offered have been
sold or which deregisters all of such securities then remaining unsold, shall be
deemed to be incorporated herein by reference and to be a part hereof from the
date of filing of such documents, except as to any portion of any future annual
or quarterly report to stockholders or document that is not deemed filed under
such provisions. For the purposes of this registration statement, any statement
in a document incorporated by reference shall be deemed to be modified or
superseded to the extent that a statement contained in this registration
statement modifies or supersedes a statement in such document. Any statement so
modified or superseded shall not be deemed, except as so modified or superseded,
to constitute a part of this registration statement.

Item 6. Indemnification of Directors and Officers.

        (a) Section 145 of the Delaware General Corporation Law makes provision
for the indemnification of officers and directors in terms sufficiently broad to
include indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the Securities Act of 1933,
as amended (the "1933 Act"). Section 145 of the Delaware General Corporation law
permits indemnification by the corporation of its officers and directors against
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by them in connection with actions
or proceedings against them if they acted in good faith and in a manner they
reasonably believed to be in or not opposed to the best interests of the
corporation, and, with respect to any criminal action or proceeding, had no
reason to believe their conduct was unlawful. Section 145 provides that no
indemnification may be made, however, without court approval, in respect of any
claim as to which the officer or director is adjudged to be liable to the
corporation. Such indemnification provisions of Delaware law are expressly not
exclusive of any other rights which the officers or directors may have under the
corporation's by-laws or agreements, pursuant to the vote of stockholders or
disinterested directors or otherwise.

        (b) The Restated Certificate of Incorporation of the Registrant provides
that the Registrant will, to the maximum extent permitted by law, indemnify each
of its officers and directors against expenses, judgments, fines, settlements
and other amounts actually and reasonably incurred in connection with any
proceeding arising by reason of the fact any such person is or was a director or
officer of the Registrant. The Company also carries directors and officers
liability insurance.

        (c) The Company has entered into separate indemnification agreements
with its directors and officers. These agreements require the Company, among
other things, to indemnify them against liabilities that may arise by reason of
their status or service as directors or officers (other than liabilities arising
from actions not taken in good faith or in a manner the indemnitee believed to
be opposed to the best interests of the Company), and to advance their expenses
incurred as a result of any proceeding against them as to which they could be
indemnified. Insofar as indemnification for liabilities arising under the 1933
Act may be permitted to directors, officers or persons controlling the Company
pursuant to the foregoing provisions, the Company has been informed that in the
opinion of the Commission, such indemnification is against public policy as
expressed in the 1933 Act and is therefore unenforceable.


                                       2
<PAGE>   3

Item 8. Exhibits.

        The following exhibits are filed as part of this Registration Statement:

        Number               Description
        ------               -----------

         4.1          Stock Awards Plan, As Amended (the "Awards Plan").

         4.2          Employee Stock Purchase Plan.

         5.1          Opinion of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation, Counsel to the Registrant.

        23.1          Consent of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation (included in the Opinion filed as Exhibit 
                      5.1).

        23.2          Consent of KPMG Peat Marwick LLP, independent auditors.

        24.1          Power of Attorney (included on signature page to the
                      Registration Statement at page S-1).

Item 9. Undertakings.

        (a)    The undersigned Registrant hereby undertakes:

               (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                        (i) To include any prospectus required by Section
                10(a)(3) of the Securities Act;

                        (ii) To reflect in the prospectus any facts or events
                arising after the effective date of this Registration Statement
                (or the most recent post-effective amendment thereof) which,
                individually or in the aggregate, represent a fundamental change
                in the information set forth in the registration statement;

                        (iii) To include any material information with respect
                to the plan of distribution not previously disclosed in the
                registration statement or any material change to such
                information in the registration statement.

               Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) shall
not apply if the information required to be included in a post-effective
amendment by these paragraphs is contained in periodic reports filed by the
registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in the registration statement.

               (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

               (3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

        (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.


                                       3
<PAGE>   4

        (c) Insofar as indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons
of the Registrant pursuant to the foregoing provisions, or otherwise, the
Registrant has been advised that in the opinion of the Securities and Exchange
Commission such indemnification is against public policy as expressed in the
Securities Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
Registrant of expenses incurred or paid by a director, officer or controlling
person of the Registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Securities
Act and will be governed by the final adjudication of such issue.


                                       4
<PAGE>   5

                                   SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended,
the Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Costa Mesa, State of California, on the 30th day
of October, 1998.

                                         QLOGIC CORPORATION



                                          By: /s/  Thomas R. Anderson
                                              ----------------------------------
                                              Thomas R. Anderson
                                              Vice President and Chief 
                                              Financial Officer

                                POWER OF ATTORNEY

        We, the undersigned directors and officers of QLogic Corporation, do
hereby constitute and appoint H.K. Desai and Thomas R. Anderson, or either of
them, our true and lawful attorneys and agents, to sign for us or any of us in
our names and in the capacities indicated below, any and all amendments
(including post-effective amendments) to this Registration Statement, and to
file the same, with all exhibits thereto and other documents required in
connection therewith, and to do any and all acts and things in our names and in
the capacities indicated below, which said attorneys and agents, or either of
them, may deem necessary or advisable to enable said corporation to comply with
the Securities Act of 1933, as amended, and any rules, regulations, and
requirements of the Securities and Exchange Commission, in connection with this
Registration Statement; and we do hereby ratify and confirm all that the said
attorneys and agents, or either of them, shall do or cause to be done by virtue
hereof.

        Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the date indicated.

<TABLE>
<CAPTION>
              SIGNATURE                                TITLE                              DATE
              ---------                                -----                              ----
<S>                                        <C>                                       <C>


         /s/   GARY LIEBL                  Chairman of the Board of Directors        October 28, 1998
--------------------------------------
               GARY E. LIEBL



         /s/   H.K. DESAI                  President and Chief Executive Officer     October 28, 1998
--------------------------------------     (Principal Executive Officer)
               H.K. DESAI        



         /s/   THOMAS R. ANDERSON          Vice President and Chief Financial        October 28, 1998
--------------------------------------     Officer (Principal Financial and
               THOMAS R. ANDERSON          Accounting Officer)



         /s/   MICHAEL R. MANNING          Secretary and Treasurer                   October 28, 1998
--------------------------------------
               MICHAEL R. MANNING
</TABLE>


                                       5
<PAGE>   6

<TABLE>
<CAPTION>
              SIGNATURE                                TITLE                              DATE
              ---------                                -----                              ----
<S>                                        <C>                                       <C>



         /s/   JAMES A. BIXBY              Director                                  October 28, 1998
--------------------------------------
               JAMES A. BIXBY



         /s/   CAROL L. MILTNER            Director                                  October 28, 1998
--------------------------------------
               Carol L. Miltner



         /s/   GEORGE D. WELLS             Director                                  October 28, 1998
--------------------------------------
               GEORGE D. WELLS
</TABLE>

                                        6
<PAGE>   7

                                  EXHIBIT INDEX

<TABLE>
<CAPTION>
                                                                                Sequential
        Number               Description                                        Page Number
        ------               -----------                                        -----------
<S>                   <C>                                                       <C>

         4.1          Stock Awards Plan, As Amended

         4.2          Employee Stock Purchase Plan

         5.1          Opinion of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation, Counsel to the Registrant.

        23.1          Consent of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation (included in the Opinion filed as Exhibit
                      5.1).

        23.2          Consent of KPMG Peat Marwick LLP, independent auditors.

        24.1          Power of Attorney (included on signature page to the
                      Registration Statement at page S-1).
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 20673}]
{"company-data": {"conformed-name": "QLOGIC CORP", "cik": "0000918386", "assigned-sic": "3674", "irs-number": "330537669", "state-of-incorporation": "DE", "fiscal-year-end": "0330"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-66407", "film-number": "98734289"}, "business-address": {"street1": "3545 HARBOR BLVD", "city": "COSTA MESA", "state": "CA", "zip": "92626", "phone": "7144382200"}, "mail-address": {"street1": "3545 HARBOR BOULEVARD", "city": "COSTA MESA", "state": "CA", "zip": "92626"}, "former-company": {"former-conformed-name": "Q LOGIC CORP", "date-changed": "19940201"}}
1

   As Filed With the Securities and Exchange Commission on October 30, 1998.
                                                Registration No. 333-___________

================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON. D.C. 20549

                                   ----------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                                   ----------

                               QLOGIC CORPORATION
             (Exact name of registrant as specified in its charter)

           DELAWARE                                      33-0537669
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
 incorporation or organization)

               3545 HARBOR BOULEVARD, COSTA MESA, CALIFORNIA 92626
               (Address of Principal Executive Offices) (Zip Code)

                                   ----------

                          EMPLOYEE STOCK PURCHASE PLAN
                                STOCK AWARDS PLAN
                           (Full titles of the plans)

                                   ----------

         Thomas R. Anderson, Vice President and Chief Financial Officer
                               QLogic Corporation
                              3545 Harbor Boulevard
                          Costa Mesa, California 92626
                     (Name and address of agent for service)

                                 (714) 438-2200
          (Telephone number, including area code, of agent for service)

                                    Copy to:
                               Nick E. Yocca, Esq.
           Stradling Yocca Carlson & Rauth, a Professional Corporation
      660 Newport Center Drive, Suite 1600, Newport Beach, California 92660
                                 (949) 725-4000

                         CALCULATION OF REGISTRATION FEE
===============================================================================================
                                        Proposed Maximum   Proposed Maximum 
Title of Securities    Amount To Be      Offering Price        Aggregate         Amount of
 To Be Registered      Registered(1)       Per Share        Offering Price    Registration Fee
===============================================================================================
Common Stock,
  $0.10 par value     675,000 shares       $86.625(2)      $58,471,875.00(2)     $16,256.00
===============================================================================================
(1) Includes additional shares of Common Stock that may become issuable
     pursuant to the anti-dilution adjustment provisions of the Employee Stock
     Purchase Plan (the "Purchase Plan") and the Stock Awards Plan (the "Awards
     Plan").

     (2) In accordance with Rule 457(h), the aggregate offering price of 300,000
     shares of Common Stock registered hereby which the Registrant is authorized
     to issue under the Purchase Plan and of the additional 375,000 shares which
     the Registrant is authorized to issue under the Awards Plan is estimated
     solely for purposes of calculating the registration fee on the basis of the
     price of securities of the same class, as determined in accordance with
     Rule 457(c), using the average of the high and low price reported by the
     Nasdaq National Market for the Common Stock on October 26, 1998, which was
     $86.625 per share.

PAGE 1 OF ___ PAGES                                   EXHIBIT INDEX ON PAGE [__]
2

PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

        This registration statement relates to both the Stock Awards Plan, as
amended ("Awards Plan"), of the Registrant and the Employee Stock Purchase Plan
("ESPP") of the Registrant. An aggregate of 1,350,000 shares of the Registrant's
common stock issuable pursuant to the Awards Plan have previously been
registered on Form S-8, Registration No. 33-75814, filed February 28, 1994, and
Form S-8, Registration No. 333-13137, filed October 1, 1996, and the contents of
both such registration statements are incorporated by reference except as
revised herein. On August 1, 1997, the Registrant's Board of Directors amended
the Awards Plan to further increase the number of shares issuable thereunder by
375,000, from 1,350,000 shares to 1,725,000 shares, and on August 11, 1997,
amended the Awards Plan to establish 500,000 shares as the maximum number of
derivative securities and shares of common stock that may be granted to any one
participant in any calendar year. Both such amendments were adopted subject to
stockholder approval, which was obtained at the Registrant's Annual Meeting of
Stockholders held on September 23, 1997. Pursuant to General Instruction E of
Form S-8, this registration statement registers the additional 375,000 shares
issuable under the Awards Plan.

Item 3.  Incorporation of Documents by Reference.

        The following documents are incorporated herein by reference:

        (a) The contents of the Registrant's Registration Statement on Form S-8
(Registration No. 33-75814) as filed with the Securities and Exchange Commission
(the "Commission") on February 28, 1994;

        (b) The contents of the Registrant's Registration Statement on Form S-8
(Registration No. 333-13137) as filed with the Commission on October 1, 1996;

        (c) The Registrant's Annual Report on Form 10-K for its fiscal year
ended March 29, 1998, filed with the Commission under the Securities Exchange
Act of 1934, as amended (the "Exchange Act") on June 17, 1998;

        (d) The Registrant's Quarterly Report on Form 10-Q for its fiscal
quarter ended June 28, 1998, filed with the Commission under the Exchange Act on
August 11, 1998;

        (e) All other reports filed by the Registrant pursuant to Section 13(a)
or 15(d) of the Exchange Act since the end of the fiscal year covered by the
report referred to in (c) above;

        (f) The description of the Registrant's Common Stock that is contained
in the Registrant's Registration Statement on Form 10 (Commission file number
0-23298) filed with the Commission under the Exchange Act on February 15, 1994;

        (g) The description of the Rights to Purchase Series A Junior
Participating Preferred Stock (the "Rights") and of the Series A Junior
Participating Preferred Stock, par value $0.001 per share, that is contained in
the Registrant's Registration Statement on Form 8-A filed with the Commission
under Section 12 of the Exchange Act on June 19, 1996, including any amendment
or report filed for the purpose of updating that description.

        All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a
post-effective amendment which indicates that all securities offered have been
sold or which deregisters all of such securities then remaining unsold, shall be
deemed to be incorporated herein by reference and to be a part hereof from the
date of filing of such documents, except as to any portion of any future annual
or quarterly report to stockholders or document that is not deemed filed under
such provisions. For the purposes of this registration statement, any statement
in a document incorporated by reference shall be deemed to be modified or
superseded to the extent that a statement contained in this registration
statement modifies or supersedes a statement in such document. Any statement so
modified or superseded shall not be deemed, except as so modified or superseded,
to constitute a part of this registration statement.

Item 6. Indemnification of Directors and Officers.

        (a) Section 145 of the Delaware General Corporation Law makes provision
for the indemnification of officers and directors in terms sufficiently broad to
include indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the Securities Act of 1933,
as amended (the "1933 Act"). Section 145 of the Delaware General Corporation law
permits indemnification by the corporation of its officers and directors against
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by them in connection with actions
or proceedings against them if they acted in good faith and in a manner they
reasonably believed to be in or not opposed to the best interests of the
corporation, and, with respect to any criminal action or proceeding, had no
reason to believe their conduct was unlawful. Section 145 provides that no
indemnification may be made, however, without court approval, in respect of any
claim as to which the officer or director is adjudged to be liable to the
corporation. Such indemnification provisions of Delaware law are expressly not
exclusive of any other rights which the officers or directors may have under the
corporation's by-laws or agreements, pursuant to the vote of stockholders or
disinterested directors or otherwise.

        (b) The Restated Certificate of Incorporation of the Registrant provides
that the Registrant will, to the maximum extent permitted by law, indemnify each
of its officers and directors against expenses, judgments, fines, settlements
and other amounts actually and reasonably incurred in connection with any
proceeding arising by reason of the fact any such person is or was a director or
officer of the Registrant. The Company also carries directors and officers
liability insurance.

        (c) The Company has entered into separate indemnification agreements
with its directors and officers. These agreements require the Company, among
other things, to indemnify them against liabilities that may arise by reason of
their status or service as directors or officers (other than liabilities arising
from actions not taken in good faith or in a manner the indemnitee believed to
be opposed to the best interests of the Company), and to advance their expenses
incurred as a result of any proceeding against them as to which they could be
indemnified. Insofar as indemnification for liabilities arising under the 1933
Act may be permitted to directors, officers or persons controlling the Company
pursuant to the foregoing provisions, the Company has been informed that in the
opinion of the Commission, such indemnification is against public policy as
expressed in the 1933 Act and is therefore unenforceable.

                                       2
3

Item 8. Exhibits.

        The following exhibits are filed as part of this Registration Statement:

        Number               Description
        ------               -----------

         4.1          Stock Awards Plan, As Amended (the "Awards Plan").

         4.2          Employee Stock Purchase Plan.

         5.1          Opinion of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation, Counsel to the Registrant.

        23.1          Consent of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation (included in the Opinion filed as Exhibit 
                      5.1).

        23.2          Consent of KPMG Peat Marwick LLP, independent auditors.

        24.1          Power of Attorney (included on signature page to the
                      Registration Statement at page S-1).

Item 9. Undertakings.

        (a)    The undersigned Registrant hereby undertakes:

               (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                        (i) To include any prospectus required by Section
                10(a)(3) of the Securities Act;

                        (ii) To reflect in the prospectus any facts or events
                arising after the effective date of this Registration Statement
                (or the most recent post-effective amendment thereof) which,
                individually or in the aggregate, represent a fundamental change
                in the information set forth in the registration statement;

                        (iii) To include any material information with respect
                to the plan of distribution not previously disclosed in the
                registration statement or any material change to such
                information in the registration statement.

               Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) shall
not apply if the information required to be included in a post-effective
amendment by these paragraphs is contained in periodic reports filed by the
registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in the registration statement.

               (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

               (3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

        (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.

                                       3
4

        (c) Insofar as indemnification for liabilities arising under the
Securities Act may be permitted to directors, officers and controlling persons
of the Registrant pursuant to the foregoing provisions, or otherwise, the
Registrant has been advised that in the opinion of the Securities and Exchange
Commission such indemnification is against public policy as expressed in the
Securities Act and is, therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment by the
Registrant of expenses incurred or paid by a director, officer or controlling
person of the Registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in
connection with the securities being registered, the Registrant will, unless in
the opinion of its counsel the matter has been settled by controlling precedent,
submit to a court of appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in the Securities
Act and will be governed by the final adjudication of such issue.

                                       4
5

                                   SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, as amended,
the Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
registration statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Costa Mesa, State of California, on the 30th day
of October, 1998.

                                         QLOGIC CORPORATION

                                          By: /s/  Thomas R. Anderson
                                              ----------------------------------
                                              Thomas R. Anderson
                                              Vice President and Chief 
                                              Financial Officer

                                POWER OF ATTORNEY

        We, the undersigned directors and officers of QLogic Corporation, do
hereby constitute and appoint H.K. Desai and Thomas R. Anderson, or either of
them, our true and lawful attorneys and agents, to sign for us or any of us in
our names and in the capacities indicated below, any and all amendments
(including post-effective amendments) to this Registration Statement, and to
file the same, with all exhibits thereto and other documents required in
connection therewith, and to do any and all acts and things in our names and in
the capacities indicated below, which said attorneys and agents, or either of
them, may deem necessary or advisable to enable said corporation to comply with
the Securities Act of 1933, as amended, and any rules, regulations, and
requirements of the Securities and Exchange Commission, in connection with this
Registration Statement; and we do hereby ratify and confirm all that the said
attorneys and agents, or either of them, shall do or cause to be done by virtue
hereof.

        Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the date indicated.
SIGNATURE                                TITLE                              DATE
              ---------                                -----                              ----
/s/   GARY LIEBL                  Chairman of the Board of Directors        October 28, 1998
--------------------------------------
               GARY E. LIEBL

         /s/   H.K. DESAI                  President and Chief Executive Officer     October 28, 1998
--------------------------------------     (Principal Executive Officer)
               H.K. DESAI        

         /s/   THOMAS R. ANDERSON          Vice President and Chief Financial        October 28, 1998
--------------------------------------     Officer (Principal Financial and
               THOMAS R. ANDERSON          Accounting Officer)

         /s/   MICHAEL R. MANNING          Secretary and Treasurer                   October 28, 1998
--------------------------------------
               MICHAEL R. MANNING
5
6
SIGNATURE                                TITLE                              DATE
              ---------                                -----                              ----
/s/   JAMES A. BIXBY              Director                                  October 28, 1998
--------------------------------------
               JAMES A. BIXBY

         /s/   CAROL L. MILTNER            Director                                  October 28, 1998
--------------------------------------
               Carol L. Miltner

         /s/   GEORGE D. WELLS             Director                                  October 28, 1998
--------------------------------------
               GEORGE D. WELLS
6
7

                                  EXHIBIT INDEX
Sequential
        Number               Description                                        Page Number
        ------               -----------                                        -----------
4.1          Stock Awards Plan, As Amended

         4.2          Employee Stock Purchase Plan

         5.1          Opinion of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation, Counsel to the Registrant.

        23.1          Consent of Stradling Yocca Carlson & Rauth, a Professional
                      Corporation (included in the Opinion filed as Exhibit
                      5.1).

        23.2          Consent of KPMG Peat Marwick LLP, independent auditors.

        24.1          Power of Attorney (included on signature page to the
                      Registration Statement at page S-1).