<PAGE>
 
                                 UNITED STATES

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  FORM 10-Q/A
                              AMENDMENT NO. 1 TO
      QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
                              EXCHANGE ACT OF 1934
             For the quarterly period ended June 30, 1997

  Commission File number 1-8158


                           VARCO INTERNATIONAL, INC.
             (Exact name of registrant as specified in its charter)

       California                                   95-0472620
  (State or other jurisdiction of       (I.R.S. Employer Identification No.)
  incorporation or organization)

                   743 North Eckhoff Street, Orange, Ca 92868
                    (Address of principal executive offices)
                                   (Zip code)

                                 (714) 978-1900
              (Registrant's telephone number, including area code)

                                 Not Applicable
      (Former name, former address and former fiscal year, if changed since last
report)


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.  Yes__X__  No____

                                  31,775,922

        (Number of shares of Common Stock outstanding at June 30, 1997)
<PAGE>
 
                          PART I-FINANCIAL INFORMATION


Item 1.  Financial Statements.

     Pursuant to General Instruction D to Form 10-Q, the Condensed Consolidated
Statements of Cash Flows, Condensed Consolidated Balance Sheets and Condensed
Consolidated Statements of Income of Varco International, Inc., (the "Company")
and its subsidiaries included in the registrant's Second Quarter Report to
Shareholders for the three months ended June 30, 1997, filed as Exhibit 19
hereto are incorporated herein by reference.  Such financial statements should
be read in light of the following:

     Adjustments. The financial statements contained in Exhibit 19 hereto
include all adjustments which in the opinion of management are of a normal
recurring nature, considered necessary to present fairly the results of
operations for the interim periods presented.

     Net Income Per Share.  Net income per share is based upon an average
32,522,094 and 31,184,899 shares outstanding for the six months ended June 30,
1997, and 1996 respectively, and upon an average of 32,577,976 and 31,447,509
shares outstanding for the three months ended June 30, 1997, and 1996
respectively.

     Inventories.  The Company estimates the components of inventory at June 30,
1997, and December 31, 1996, to be as follows:

<TABLE>
<CAPTION>
                        June 30, 1997      December 31, 1996
   <S>                  <C>                <C>

   Raw Materials         $  5,849,000         $  6,545,000
   Work in Process         37,310,000           22,646,000
   Finished Goods          81,732,000           77,150,000
   LIFO Reserves          (12,479,000)         (14,468,000)
                         $112,412,000         $ 91,873,000
                         ============         ============
</TABLE>

     Fixed Assets. Fixed assets are stated net of accumulated depreciation of
$58,010,000 at June 30, 1997, and $54,534,000 at December 31, 1996.

     Common Stock and Additional Paid-In-Capital. On June 30, 1997, the Company
Common Stock account was $22,145,000 and Additional Paid-In-Capital accounts
were $123,270,000.

Item 2.  Management's Discussion and Analysis of Financial Condition and Results
of Operations.

     Pursuant to General Instruction D to Form 10-Q, Management's Discussion and
Analysis of Financial Condition and Results of Operations contained in the
registrant's Second Quarter Report to Shareholders for the three months ended
June 30, 1997, filed as Exhibit 19 hereto, is incorporated herein by reference.

<PAGE>
 
Item 6.   Exhibits and Reports on Form 8-K
 

      (a)   Exhibits

 
      4.1  Credit Agreement, dated as of June 27, 1997, among Varco
International, Inc., the financial institutions listed therein as Lenders, and
Union Bank of California, N.A., as Agent, incorporated by reference to Exhibit 
4.1 to Varco's quarterly report on Form 10-Q for the quarter ended June 30, 
1997.
 
      4.2 First Amendment to Credit Agreement, dated as of July 15, 1997, to
Credit Agreement included as Exhibit 4.1 hereto, incorporated by reference to
Exhibit 4.2 to Varco's quarterly report on Form 10-Q for the quarter ended
June 30, 1997.

     *4.3 Eighth Amendment dated as of June 9, 1997 to Credit Agreement 
included as Exhibit 4.6 to Varco's Annual Report on Form 10-K for the year ended
December 31, 1996.

     *4.4 Ninth Amendment dated as of June 27, 1997 to Credit Agreement
included as Exhibit 4.6 to Varco's Annual Report on Form 10-K for the year ended
December 31, 1996.

      10 Second Amendment to the Varco International, Inc. Supplemental
 Executive Retirement Plan, incorporated by reference to Exhibit 10 to Varco's
 quarterly report on Form 10-Q for the quarter ended June 30, 1997.

      11 Statement re computation of per share earnings for the three months and
 six months ended June 30, 1997 and 1996, incorporated by reference to Exhibit
 11 to Varco's quarterly report on Form 10-Q for the quarter ended June 30,
 1997.

     *19  Varco International, Inc. Second Quarter Report to Shareholders, Three
 Months  Ended June 30, 1997. (corrected)

      27 Financial Data Schedule, incorporated by reference to Exhibit 27 to
 Varco's quarterly report on Form 10-Q for the quarter ended June 30, 1997.

      (b)  Reports on Form 8-K.

           No reports on Form 8-K were filed during the quarter for which this
 report is filed.


* Filed herewith
<PAGE>
 
                                  SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



                                            VARCO INTERNATIONAL, INC.


Date: August 19, 1997                       By: /s/ NANCY DACK
                                            Assistant Treasurer
 



Date: August 19, 1997                       By: /s/ DONALD L. STICHLER
                                            Controller-Treasurer
                                            and Secretary
<PAGE>
 
                                 EXHIBIT INDEX


<TABLE> 
<CAPTION> 
<C>  <S> 
4.1  Credit Agreement, dated as of June 27, 1997, among Varco International,
     Inc., the financial institutions listed therein as Lenders, and Union Bank
     of California, N.A., as Agent, incorporated by reference to Exhibit 4.1 to
     Varco's quarterly report on Form 10-Q for the quarter ended June 30, 1997.
 
4.2  First Amendment to Credit Agreement, dated as of July 15, 1997, to Credit
     Agreement included as Exhibit 4.1 hereto, incorporated by reference to
     Exhibit 4.2 to Varco's quarterly report on Form 10-Q for the quarter ended
     June 30, 1997.

*4.3 Eighth Amendment dated as of June 9, 1997 to Credit Agreement included as
     Exhibit 4.6 to Varco's Annual Report on Form 10-K for the year ended
     December 31, 1996.

*4.4 Ninth Amendment dated as of June 27, 1997 to Credit Agreement included as
     Exhibit 4.6 to Varco's Annual Report on Form 10-K for the year ended
     December 31, 1996.

10   Second Amendment to the Varco International, Inc. Supplemental Executive
     Retirement Plan, incorporated by reference to Exhibit 10 to Varco's
     quarterly report on Form 10-Q for the quarter ended June 30, 1997.

11   Statement re computation of per share earnings for the three months and six
     months ended June 30, 1997 and 1996, incorporated by reference to Exhibit
     11 to Varco's quarterly report on Form 10-Q for the quarter ended June 30,
     1997.

*19  Varco International, Inc. Second Quarter Report to Shareholders, Three
     Months Ended June 30, 1997. (corrected)

27   Financial Data Schedule, incorporated by reference to Exhibit 27 to Varco's
     quarterly report on Form 10-Q for the quarter ended June 30, 1997.
</TABLE> 

* Filed herewith