EXHIBIT 99.1


FOR IMMEDIATE RELEASE

             NASDAQ INFORMS ZONAGEN THAT IT NO LONGER MEETS NATIONAL
                MARKET LISTING REQUIREMENTS AND WILL BE DELISTED

               ZONAGEN EXPECTS TO TRADE ON NASDAQ SMALLCAP MARKET

THE WOODLANDS, TEXAS - JUNE 28, 2004 - Zonagen, Inc. (Nasdaq: ZONA and PCX: ZNG)
announced today that it received a Nasdaq Staff Determination letter on June 23,
2004, indicating that Zonagen no longer complies with the minimum $10 million
stockholders' equity requirement which is necessary for continued listing on the
Nasdaq National Market. This shortfall is a result of the previously announced
and recently concluded (January 2004) self-tender offer in which the Company
repurchased 6,547,635 shares of common stock at a total cost of approximately
$14 million. As of March 31, 2004, (unaudited) and as of December 31, 2003, the
Company's stockholders' equity was $8,745,000 and $24,028,000, respectively.

As a result, the Company's shares will be delisted from Nasdaq on July 2, 2004,
unless the Company either applies for a Nasdaq SmallCap Listing, or appeals the
decision of the Staff Determination letter by June 30, 2004. Zonagen will apply
for a Nasdaq SmallCap Listing which will stay its Nasdaq National listing until
the application process is complete. Nasdaq will allow Zonagen to apply for a
SmallCap listing under the continued listing requirements. The Company believes
that it meets those listing requirements. There can be no assurances that Nasdaq
will accept Zonagen's application for a Nasdaq SmallCap Market listing. If the
application is denied, the Company believes that its stock will be eligible for
quotation on the OTC Bulletin Board.

Zonagen had communicated with Nasdaq about certain possible actions needed to
keep its common stock listed on the National Market; however, Zonagen's
management and board of directors is unwilling to undertake a dilutive financing
at this time as a means to maintain its National Market listing.

About Zonagen

Zonagen is engaged in the development of pharmaceutical products that address
diseases and conditions associated with the treatment of hormonal and
reproductive system disorders. For more information, visit Zonagen's web site at
http://www.zonagen.com.

Any statements that are not historical facts contained in this release are
forward-looking statements that involve risks and uncertainties, including but
not limited to those relating to Zonagen's ability to move to the Nasdaq
SmallCap Market and others identified in Zonagen's Annual Report on Form 10-K
for the year ended December 31, 2003, as filed with the Securities and Exchange
Commission (SEC). These documents are available on request from Zonagen or at
www.sec.gov. Zonagen disclaims any intention or obligation to update or revise
any forward-looking statements, whether as a result of new information, future
events or otherwise.

Contact:
Louis Ploth, Vice President and CFO
lploth@zonagen.com
281-719-3454