Exhibit 99.1
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                       Press Release dated April 23, 2004

            IRIS InTERNATIONAL CLOSES $12.5 million PRIVATE PLACEMENT

CHATSWORTH,  CA., April 23, 2004 - IRIS  International,  Inc. (NASDAQ:  IRIS), a
manufacturer  and  marketer  of  automated  IVD  urinalysis  systems and medical
devices used in hospitals and reference  clinical  laboratories  worldwide,  has
completed  its  previously  announced  private  placement  with new and existing
institutional  investors.  A  total  of  2,130,000  unregistered  shares  of the
Company's  common  stock  were sold,  together  with  warrants  to  purchase  an
additional  319,500 shares of its common stock, for an aggregate  purchase price
of approximately $12.5 million. The warrants have an exercise price of $7.80 per
share and a five-year term.  After deducting  estimated  closing costs and fees,
the Company received net proceeds of approximately $11.6 million.  Oppenheimer &
Co. Inc. acted as placement agent for the transaction.  The Company will proceed
to file a  registration  statement to register the common  shares and the common
shares underlying the warrants.

Cesar Garcia,  IRIS'  President and Chief  Executive  Officer,  stated,  "We are
pleased to have  closed on this  financing  which  provides  the capital to help
support  current  and future  growth.  In addition  to general  working  capital
purposes, net proceeds will be used to fund growth internally as well as through
potential selective acquisitions. In addition, the financing further strengthens
IRIS' balance sheet by eliminating all outstanding debt."

THE COMPANY

IRIS International,  Inc.  (www.proiris.com) is a leader in automated urinalysis
technology with systems in major medical institutions  throughout the world. The
Company's newest generation  iQ(R)200 fully Automated Urine Microscopy  Analyzer
utilizing image flow cytometry,  patented Automated Intelligent Microscopy (AIM)
technology and neural network-based particle recognition capabilities achieves a
significant   reduction  in  the  cost  and  time-consuming   steps  for  manual
microscopic analysis.  The Company's StatSpin(R)  subsidiary,  based in Norwood,
Mass., manufactures innovative centrifuges and blood analysis products. Advanced
Digital  Imaging  Research,  LLC  (ADIR),  based  near  Houston,  Texas,  is the
Company's imaging research and development subsidiary.

SAFE HARBOR PROVISION

This news release contains forward-looking  statements made in reliance upon the
safe harbor provisions of the Private Securities  Litigation Reform Act of 1995.
Forward-looking  statements include, but are not limited to, the Company's views
on future commercial revenues, market growth, capital requirements,  new product
introductions,  and are  generally  identified  by  phrases  such  as  "thinks,"
"anticipates,"  "believes,"  "estimates,"  "expects,"  "intends,"  "plans,"  and
similar  words.   Forward-looking   statements  are  not  guarantees  of  future
performance and are inherently  subject to uncertainties and other factors which
could  cause  actual  results  to  differ  materially  from the  forward-looking
statement. These statements are based upon, among other things, assumptions made
by, and information currently available to, management,  including  management's
own knowledge and assessment of the Company's industry,  competition and capital
requirements.  Other factors and  uncertainties  that could affect the Company's
forward-looking  statements  include,  among other things,  the  following:  the
acceptance by customers of our new iQ(R)200  product  platform,  our substantial
expansion  of  international  sales  and  our  reliance  on key  suppliers,  the
potential  need  for  changes  in  long-term  strategy  in  response  to  future
developments;  future advances in diagnostic testing methods and procedures,  as
well as potential  changes in government  regulations  and healthcare  policies,
both of which could  adversely  affect the economics of the  diagnostic  testing
procedures  automated by the Company's products;  rapid technological  change in
the microelectronics and software  industries;  and increasing  competition from
imaging and non-imaging based in-vitro diagnostic  products.  The Company refers
interested  persons to its most recent  Annual Report on Form 10-K and its other
SEC filings for a description of additional  uncertainties  and factors that may
affect  forward-looking  statements.  The Company  assumes no duty to update its
forward-looking statements.