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


       Date of Report (Date of earliest event reported): April 15, 2008

                            ZOLTEK COMPANIES, INC.
            (Exact name of registrant as specified in its charter)


   MISSOURI                         0-20600                       43-1311101
(State or other                (Commission File                (I.R.S. Employer
jurisdiction of                     Number)                     Identification
 organization)                                                      Number)


3101 MCKELVEY ROAD
ST. LOUIS, MISSOURI                                                  63044
(Address of principal executive offices)                           (Zip Code)

                                (314) 291-5110
             (Registrant's telephone number, including area code)

                                NOT APPLICABLE
         (Former name or former address if changed since last report)

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Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the Registrant under
any of the following provisions:

[ ]   Written communications pursuant to Rule 425 under the Securities Act
      (17 CFR 230.425)

[ ]   Soliciting material pursuant to Rule 14a-12 under the Exchange Act
      (17 CFR 240.14a-12)

[ ]   Pre-commencement communications pursuant to Rule 14d-2(b) under the
      Exchange Act (17 CFR 240.14d-2(b))

[ ]   Pre-commencement communications pursuant to Rule 13e-4(c) under the
      Exchange Act (17 CFR 240.13e-4(c))

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ITEM 7.01.     REGULATION FD DISCLOSURE.

            On April 15, 2008, Zoltek Companies, Inc. issued a press
release with respect to results for the quarter ended March 31, 2008.
The text of the press release is attached hereto as Exhibit 99.

            This Form 8-K, including Exhibit 99 attached hereto, shall
not be deemed "filed" for purposes of Section 18 of the Securities
Exchange Act of 1934, as amended, or otherwise subject to the
liabilities of that section.


ITEM 9.01.     FINANCIAL STATEMENTS AND EXHIBITS.

               (a) Financial statements of businesses acquired. Not applicable.
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               (b) Pro forma financial information. Not applicable.
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               (c) Exhibits. See Exhibit Index.
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                                  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.

Dated: April 15, 2008

                                             ZOLTEK COMPANIES, INC.



                                             By /s/ Zsolt Rumy
                                                ------------------------------
                                                Zsolt Rumy
                                                Chief Executive Officer


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                                 EXHIBIT INDEX
Exhibit
Number                            Description
- ------                            -----------

 99                   Press Release, dated April 15, 2008





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