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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


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                                    FORM 8-K


                                 CURRENT REPORT


                         PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934


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       DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): DECEMBER 5, 2003


                               INPUT/OUTPUT, INC.
             (Exact Name of Registrant As Specified In Its Charter)


       DELAWARE                         1-12691                  22-2286646
(State or Other Jurisdiction      (Commission File No.)       (I.R.S. Employer
   of Incorporation)                                         Identification No.)


                             12300 PARC CREST DRIVE
                              STAFFORD, TEXAS 77477
               (Address of Principal Executive Offices) (Zip Code)

                                 ( 281) 933-3339
              (Registrant's Telephone Number, Including Area Code)


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ITEM 5.  OTHER EVENTS AND REGULATION FD DISCLOSURE.

         On December 5, 2003, Input/Output, Inc., a Delaware corporation ("IO"),
issued a press release pursuant to Rule 135c under the Securities Act of 1933,
as amended (the "Securities Act"), announcing the pricing of its private
offering of $50 million aggregate principal amount of its Convertible Senior
Notes due 2008 pursuant to Rule 144A under the Securities Act. The sale of the
notes is expected to close on December 10, 2003. IO also granted the initial
purchaser of the notes a 30-day option to purchase up to an additional $10
million aggregate principal amount of the notes.

         The notes will bear interest at the rate of 5.50% per annum. The notes
are convertible into shares of I/O common stock at a conversion rate of 231.4815
shares of common stock per $1,000 principal amount of notes, which is equivalent
to an initial conversion price of $4.32 per share of common stock, subject to
adjustment in certain circumstances.

         The foregoing is qualified by reference to the press release which is
attached as Exhibit 99.1 to this Current Report on Form 8-K, which is
incorporated herein by reference.

         The information contained in this Current Report on Form 8-K, including
the exhibit hereto, is neither an offer to sell nor a solicitation of an offer
to purchase any of the notes or any shares of common stock of IO and shall not
constitute an offer, solicitation or sale in any jurisdiction in which such
offer, solicitation or sale is unlawful. The notes and any shares of common
stock of IO issuable upon conversion of the notes have not been registered under
the Securities Act or the securities or blue sky laws of any jurisdiction and,
unless registered, may not be offered or sold except pursuant to an applicable
exemption from the registration requirements of the Securities Act and
applicable securities laws of any other jurisdiction.

ITEM 7.  FINANCIAL STATEMENTS AND EXHIBITS.

         (a)      Financial statements of businesses acquired

                                 Not applicable

         (b)      Pro forma financial information

                                 Not applicable

         (c)      Exhibits

                  99.1    Press release of Input/Output Inc. dated
                          December 5, 2003.

ITEM 9.  REGULATION FD DISCLOSURE.

A. LIMITATION BY INCORPORATION BY REFERENCE

         In accordance with General Instruction B.2 of Form 8-K, the information
set forth in this Item 9 shall not be deemed to be "filed" for purposes of
Section 18 of the Securities Exchange Act of 1934, as amended or otherwise
subject to the liabilities of that section, nor shall such information be deemed
incorporated by reference in any filing under the Securities Act or the Exchange
Act, except as shall be expressly set forth by specific reference in such a
filing.

B. SUPPLEMENTAL INFORMATION

SCF NOTE AND WARRANT

         A portion of the net proceeds from the offering of notes referred to
above will be used to repay in full the approximately $16.0 million in
outstanding indebtedness under an unsecured promissory note payable to SCF-IV,
L.P., which is scheduled to mature in May 2004. We had granted to SCF-IV, L.P. a
warrant to purchase 2,673,517 shares of our common stock at $8.00 per share,
which is scheduled to expire on August 5, 2005 (the SCF Warrant). Concurrently
with the consummation of the notes offering, we expect to exchange 125,000
shares of our common stock with SCF-IV, L.P. for the SCF Warrant, in a
transaction exempt from the registration requirements under the Securities Act.



                                    SIGNATURE

         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.


                                   INPUT/OUTPUT, INC.
                                   (Registrant)



                                           /s/ [Brad Eastman]
                                   ----------------------------------------
                                                  [Brad Eastman]
                                   Vice President, Chief Administrative Officer
                                                  and Secretary




Date: December 5, 2003





                                  EXHIBIT INDEX



EXHIBIT NO.        DESCRIPTION
                
99.1               Press release of Input/Output, Inc. dated December 5, 2003.