Exhibit 99.1
FOR IMMEDIATE RELEASE                                             April 27, 2000

CONTACT:          Donald L. Rich, President & CEO             408-496-0474

Castelle Reports First Quarter 2000 Results: Positive $0.03 EPS

SANTA CLARA,  Calif.,  April 27, 2000 - CASTELLE (Nasdaq:  CSTL) today announced
financial results for the first fiscal quarter ended March 31, 2000.

Net sales for the first  quarter  of 2000 were $4.1  million,  compared  to $4.5
million  for the same period in 1999.  This  compares to net sales in the fourth
quarter of 1999 of $3.9 million, an increase of 5.3%.

The  Company  recorded  net income for the first  quarter of 2000 of $168,000 or
earnings of $0.03 per share, on a fully diluted basis, compared to a net loss of
$1.4  million  or a loss of $0.33 per share  for the same  period in 1999.  This
compares to net income in the fourth  quarter of 1999 of $114,000 or earnings of
$0.02 per share, an improvement in earnings of 47%.

The loss in the first quarter of 1999 included an $880,000 reserve primarily for
excess  inventory  related  to the print  server  product  line.  Excluding  the
additional  inventory  reserve,  the net loss for the  period  would  have  been
$531,000, or $0.12 per share.

Donald L. Rich,  President and CEO,  stated,  "We have sustained two quarters of
profitability which were supported by the introduction of an enhanced Fax Server
product line with improved gross margins,  the  implementation of cost reduction
programs and controlled operating expenses. Our cash flow and balance sheet have
continued to improve in the first quarter of 2000.  We have  adjusted  inventory
levels to match customer demand, decreased the average Days Sales Outstanding to
31 and brought current our accounts payable, while maintaining a cash balance of
$4.4  million as of March 31,  2000.  Castelle's  new cost  structure  and sales
channel  strategy  have  allowed  the  Company to better  compete in its current
markets. We are committed to broadening our market opportunity by developing and
introducing additional server appliance products in future quarters."

About Castelle

Founded in 1987, Castelle develops server appliances  providing office messaging
solutions and other shared services.  The company  pioneered server  appliances,
establishing  a benchmark for "plug and play" and  ease-of-use  with its fax and
print server product  families.  Castelle products are installed in the majority
of Fortune 1000 companies and in small and medium-sized  business  worldwide and
are  available  through  a  worldwide   network  of  distributors,   value-added
resellers,   e-commerce   retailers,   and  systems  integrators.   Castelle  is
headquartered  in  Santa  Clara  and  can  be  reached  at   408-496-0474,   fax
408-496-0502 or www.castelle.com.

Forward-Looking Statements

This press release  contains  forward-looking  statements that involve risks and
uncertainties,  relating  to the  future  events,  including  the  effect of the
Company's  cost  structure on its business  going forward and the ability of the
Company  to  continue  to (i)  develop  and  introduce  new  products,  (ii)  be
profitable,  (iii) control  operating  expenses,  (iv) maintain proper inventory
levels,  and (iv) keep accounts payable current.  Actual events or the Company's
results  may  differ  materially  from the events or  results  discussed  in the
forward-looking   statements  for  a  number  of  reasons   including,   without
limitation,  the timely development,  acceptance and pricing of new products and
the general  economic  conditions  as they affect the Company's  customers.  The
Company  assumes  no  obligation  to  update  the  forward-looking  information.
Investors  are  referred  to the  full  discussion  of risks  and  uncertainties
associated with  forward-looking  statements contained in the Company's 10-K for
the fiscal year ended December 31, 1999.
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