EXHIBIT 31
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                                CERTIFICATION

         I, Zsolt Rumy, certify that:

         1. I have reviewed this annual report on Form 10-K of Zoltek
Companies, Inc.;

         2. Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to
make the statements made, in light of the circumstances under which such
statements were made, not misleading with respect to the period covered by
this report;

         3. Based on my knowledge, the financial statements, and other
financial information included in this report, fairly present in all
material respects the financial condition, results of operations and cash
flows of the registrant as of, and for, the periods presented in this
report;

         4. I am responsible for establishing and maintaining disclosure
controls and procedures (as defined in Exchange Act Rules 13a-15(e) and
15d-15(e)) for the registrant and have:

         (a) Designed such disclosure controls and procedures, or caused
such disclosure controls and procedures to be designed under my supervision,
to ensure that material information relating to the registrant, including
its consolidated subsidiaries, is made known to me by others within those
entities, particularly during the period in which this quarterly report is
being prepared;

         (b) Evaluated the effectiveness of the registrant's disclosure
controls and procedures and presented in this report my conclusions about
the effectiveness of the disclosure controls and procedures, as of the end
of the period covered by this quarterly report based on such evaluation; and

         (c) Disclosed in this report any change in the registrant's
internal control over financial reporting that occurred during the
registrant's most recent fiscal quarter that has materially affected, or is
reasonably likely to materially affect, the registrant's internal control
over financial reporting; and

         5. I have disclosed, based on my most recent evaluation of internal
control over financial reporting, to the registrant's auditors and the audit
committee of the registrant's board of directors (or persons performing the
equivalent functions):

         (a) All significant deficiencies and material weaknesses in the
design or operation of internal control over financial reporting which are
reasonably likely to adversely affect the registrant's ability to record,
process, summarize and report financial information; and

         (b) Any fraud, whether or not material, that involves management or
other employees who have a significant role in the registrant's internal
control over financial reporting.

Date:  January 12, 2004

                               By: /s/  Zsolt Rumy
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                                        Zsolt Rumy
                                        Chief Executive Officer
                                        Chief Financial Officer