SECURITIES AND EXCHANGE COMMISSION
                        Washington, D.C. 20549


                             SCHEDULE 13G

               Under the Securities Exchange Act of 1934


                          (Amendment No. 5)*



                         KLA -Tencor Corporation

                             (Name of Issuer)

                               Common Stock

                      (Title of Class of Securities)

                                482480100

                              (CUSIP Number)

                            December 31, 2001

         (Date of Event Which Requires Filing of This Statement)


Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
[X] Rule 13d-1(b)
[ ] 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 5
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 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

                  12,449,040


              6   SHARED VOTING POWER
 NUMBER OF
   SHARES
                  NONE
BENEFICIALL
 Y OWNED BY
              7   SOLE DISPOSITIVE POWER
    EACH
 REPORTING
                  14,243,300
   PERSON
   WITH:

              8   SHARED DISPOSITIVE POWER

                  NONE


 9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     14,243,300   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

     7.7%


 12  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

     HC









CUSIP: 482480100                                                Page 2 of 5
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                  SECURITIES AND EXCHANGE COMMISSION
                         Washington, DC 20549

                             Schedule 13G
               Under the Securities Exchange Act of 1934

Amendment No. 5

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.

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:
       (g)   [X]   A parent holding company or control person in
            accordance with section 240.13d-1(b)(1)(ii)(G).

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 page 2

       (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 3 of 5
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       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.

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 is a bank as defined in
          Section 3(a)(6) of the Act and a wholly owned subsidiary of
          Capital Group International, Inc.

       2. 
          Capital International Limited (CIL) does not fall within any
          of the categories described in Rule 13d-1-(b)(ii)(A-F) but
          its holdings of any reported securities come within the five
          percent limitation as set forth in a December 15, 1986 no-
          action letter from the Staff of the Securities and Exchange
          Commission to The Capital Group Companies, Inc. CIL is a
          wholly owned subsidiary of Capital Group International, Inc.

       3. 
          Capital International S.A. (CISA) does not fall within any of
          the categories described in Rule 13d-1-(b)(ii)(A-F) but its
          holdings of any reported securities come within the five
          percent limitation as set forth in a December 15, 1986 no-
          action letter from the Staff of the Securities and Exchange
          Commission to The Capital Group Companies, Inc. CISA is a
          wholly owned subsidiary of Capital Group International, Inc.

       4. 
          Capital International Research and Management, Inc. dba
          Capital International, Inc. is an investment adviser
          registered under Section 203 of the Investment Advisers Act
          of 1940 and is a wholly owned subsidiary of Capital Group
          International, Inc.

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

Item 9   Notice of Dissolution of Group:  N/A

Item 10   Certification


CUSIP: 482480100                                                Page 4 of 5

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       and belief, the securities referred to above were acquired and
       are held in the ordinary course of business and 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.

   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:          February 11, 2002


        Signature:     *David I. Fisher

        Name/Title:    David I. Fisher, Chairman

                       Capital Group International, Inc.




        *By    /s/ Kristine M. Nishiyama

               Kristine M. Nishiyama
               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



























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