SECURITIES AND EXCHANGE COMMISSION
                        Washington, D.C. 20549


                             SCHEDULE 13G

               Under the Securities Exchange Act of 1934


                          (Amendment No. 6)*



                         KLA -Tencor Corporation

                             (Name of Issuer)

                               Common Stock

                      (Title of Class of Securities)

                                482480100

                              (CUSIP Number)

                             October 2, 2002

         (Date of Event Which Requires Filing of This Statement)


Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
[ ] Rule 13d-1(b)
[X] Rule 13d-1(c)
[ ] Rule 13d-1(d)


*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class
of securities, and for any subsequent amendment containing information
which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of
that section of the Act but shall be subject to all other provisions of
the Act (however, see the Notes).



















CUSIP: 482480100                                                Page 1 of 7



 1   NAMES OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
     Capital Group International, Inc.
     95-4154357

 2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
     INSTRUCTIONS)                                                 (a)   

                                                                    (b)   

 3   SEC USE ONLY




 4   CITIZENSHIP OR PLACE OF ORGANIZATION

     California


              5   SOLE VOTING POWER

                  21,121,770


              6   SHARED VOTING POWER
 NUMBER OF
   SHARES
                  NONE
BENEFICIALL
 Y OWNED BY
              7   SOLE DISPOSITIVE POWER
    EACH
 REPORTING
                  24,024,930
   PERSON
   WITH:

              8   SHARED DISPOSITIVE POWER

                  NONE


 9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     24,024,930   Beneficial ownership disclaimed pursuant to Rule 13d-4


 10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
     (SEE INSTRUCTIONS)



 11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

     12.7%


 12  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

     HC







CUSIP: 482480100                                                Page 2 of 7
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 1   NAMES OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
     Capital Guardian Trust Company
     95-2553868

 2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
     INSTRUCTIONS)                                                 (a)   

                                                                    (b)   

 3   SEC USE ONLY




 4   CITIZENSHIP OR PLACE OF ORGANIZATION

     California


              5   SOLE VOTING POWER

                  9,523,340


              6   SHARED VOTING POWER
 NUMBER OF
   SHARES
                  NONE
BENEFICIALL
 Y OWNED BY
              7   SOLE DISPOSITIVE POWER
    EACH
 REPORTING
                  12,426,500
   PERSON
   WITH:

              8   SHARED DISPOSITIVE POWER

                  NONE


 9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     12,426,500   Beneficial ownership disclaimed pursuant to Rule 13d-4


 10  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
     (SEE INSTRUCTIONS)



 11  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9

     6.6%


 12  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

     CO







CUSIP: 482480100                                                Page 3 of 7
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                  SECURITIES AND EXCHANGE COMMISSION
                         Washington, DC 20549

                             Schedule 13G
               Under the Securities Exchange Act of 1934


Amendment No. 6

Item 1(a)   Name of issuer:
       KLA -Tencor Corporation

Item 1(b)   Address of issuer's principal executive offices:
       160 Rio Robles
       San Jose, CA  95134

Item 2(a)   Name of person(s) filing:
       Capital Group International, Inc. and Capital Guardian Trust
       Company

Item 2(b)   Address or principal business office or, if none,
       residence:
       11100 Santa Monica Blvd.
       Los Angeles, CA  90025

Item 2(c)   Citizenship:   N/A

Item 2(d)   Title of class of securities:
       Common Stock

Item 2(e)   CUSIP No.:
       482480100

Item 3   If this statement is filed pursuant to sections 240.13d-1(b)
       or 240.13d-2(b) or (c), check whether the person filings is a:
       N/A

Item 4   Ownership

       Provide the following information regarding the aggregate
       number and percentage of the class of securities of the issuer
       identified in Item 1.

       See pages 2 and 3

       (a)    Amount beneficially owned:
       (b)    Percent of class:
       (c)    Number of shares as to which the person has:
       (i)    Sole power to vote or to direct the vote:
       (ii)   Shared power to vote or to direct the vote:
       (iii)  Sole power to dispose or to direct the disposition of:
       (iv)   Shared power to dispose or to direct the disposition of:







CUSIP: 482480100                                                Page 4 of 7
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       Capital Group International, Inc. is the parent holding company
       of a group of investment management companies that hold
       investment power and, in some cases, voting power over the
       securities reported in this Schedule 13G.  The investment
       management companies, which include a "bank" as defined in
       Section 3(a)6 of the Securities Exchange Act of 1934 (the
       "Act") and several investment advisers registered under Section
       203 of the Investment Advisers Act of 1940, provide investment
       advisory and management services for their respective clients
       which include registered investment companies and institutional
       accounts.  Capital Group International, Inc. does not have
       investment power or voting power over any of the securities
       reported herein; however, Capital Group International, Inc. may
       be deemed to "beneficially own" such securities by virtue of
       Rule 13d-3 under the Act.

       Capital Guardian Trust Company, a bank as defined in Section
       3(a)6 of the Act is deemed to be the beneficial owner of
       12,426,500 shares or 6.6% of the 189,114,000 shares of Common
       Stock believed to be outstanding as a result of its serving as
       the investment manager of various institutional accounts.

Item 5   Ownership of 5 percent or Less of a Class.  If this statement
       is being filed to report the fact that as of the date hereof
       the reporting person has ceased to be the beneficial owner of
       more than 5 percent of the class of securities, check the
       following: [ ]

Item 6   Ownership of More than 5% on Behalf of Another Person: N/A

Item 7   Identification and Classification of the Subsidiary Which
       Acquired the Security Being Reported on By the Parent Holding
       Company or Control Person.

       1. 
          Capital Guardian Trust Company (CGTC)

       2. 
          Capital International Limited (CIL)

       3. 
          Capital International S.A. (CISA)

       4. 
          Capital International Research and Management, Inc. dba
          Capital International, Inc. (CII)

Item 8   Identification and Classification of Members of the Group:
       N/A

Item 9   Notice of Dissolution of Group:  N/A

Item 10   Certification

       By signing below I certify that, to the best of my knowledge
       and belief, the securities referred to above were not acquired
       and are not held for the purpose of or with the effect of
       changing or influencing the control of the issuer of the
       securities and were not acquired and are not held in connection
       with or as a participant in any transaction having that purpose
       or effect.



CUSIP: 482480100                                                Page 5 of 7



   Signature

       After reasonable inquiry and to the best of my knowledge and
       belief, I certify that the information set forth in this
       statement is true, complete and correct.



        Date:          October 10, 2002


        Signature:     *David I. Fisher

        Name/Title:    David I. Fisher, Chairman

                       Capital Group International, Inc.


        Date:          October 10, 2002


        Signature:     *David I. Fisher

        Name/Title:    David I. Fisher, Chairman

                       Capital Guardian Trust Company




        *By    /s/ Michael J. Downer

               Michael J. Downer
               Attorney-in-fact

               Signed pursuant to a Power of Attorney dated December
               19, 2000 included as an Exhibit to Schedule 13G filed
               with the Securities and Exchange Commission by Capital
               Group International, Inc. on February 9, 2001 with
               respect to Abitibi-Consolidated Inc.



























CUSIP: 482480100                                                Page 6 of 7


                               AGREEMENT

                            Los Angeles, CA
                           October 10, 2002

  Capital Group International, Inc. ("CGII") and Capital Guardian
Trust Company ("CGTC") hereby agree to file a joint statement on
Schedule 13G under the Securities Exchange Act of 1934 (the "Act") in
connection with their beneficial ownership of Common Stock issued by
KLA -Tencor Corporation.

  CGII and CGTC state that they are each entitled to individually use
Schedule 13G pursuant to Rule 13d-1(c) of the Act.

  CGII and CGTC are each responsible for the timely filing of the
statement and any amendments thereto, and for the completeness and
accuracy of the information concerning each of them contained therein
but are not responsible for the completeness or accuracy of the
information concerning the others.



                 CAPITAL GROUP INTERNATIONAL, INC.

                 BY:              *David I. Fisher

                                   David I. Fisher, Chairman
                                   Capital Group International,
                                   Inc.


                 CAPITAL GUARDIAN TRUST COMPANY

                 BY:              *David I. Fisher

                                   David I. Fisher, Chairman
                                   Capital Guardian Trust Company


*By  /s/ Michael J. Downer

     Michael J. Downer
     Attorney-in-fact

     Signed pursuant to a Power of Attorney dated December 19, 2000
     included as an Exhibit to Schedule 13G filed with the Securities
     and Exchange Commission by Capital Group International, Inc. on
     February 9, 2001 with respect to Abitibi-Consolidated Inc.

















CUSIP: 482480100                                                Page 7 of 7