Corporation: Investors and Media: Cyanotech Corporation Russell Communications Group Jeffrey H. Sakamoto Bruce Russell (808) 326-1353 (310) 559-4955 x101 jsakamoto@cyanotech.com brucerusse

Corporation Announces

Resignation of Jeffrey H. Sakamoto, Chief Financial Officer

KAILUA KONA, Hawaii (October 19, 2005) Cyanotech Corporation (Nasdaq

Capital Market: CYAN News), a world leader in producing high-value natural

products from microalgae, today announced that Jeffrey H. Sakamoto has resigned

as Chief Financial Officer of the Company effective November 25, 2005 to pursue

another career opportunity. Mr. Sakamoto joined Cyanotech in 1995, became

Controller in 1997 and has served as Chief Financial Officer, Vice

President-Finance & Administration, Secretary and Treasurer since March

I deeply appreciate Jeff's service to Cyanotech during the past 10

years, said Gerald R. Cysewski, Ph.D., Chairman, President and Chief Executive

Officer. He has contributed to the

Company at multiple levels during his tenure, particularly in presenting the

financial results of the Company in written reports and during our quarterly

investor presentations. Our operations

have benefited from his participation and we wish him the best in his future

Cyanotech has begun the search for a new financial officer and

anticipates a smooth transition.

Cyanotech Corporation, a world leader in

microalgal technology, produces BioAstin natural astaxanthin and Spirulina

Pacifica all-natural, functional nutrients that enhance human health and

nutrition, providing significant antioxidant, anti-inflammatory and immune

response benefits. The Company s other

compounds, such as NatuRose natural astaxanthin, promote animal nutrition and

health, primarily in aquaculture.

Cyanotech extracts these compounds from microalgae grown at its 90-acre

facility in Hawaii using proprietary processes, and distributes them to

nutraceutical, nutritional supplement, cosmeceutical and aquaculture feed

makers and marketers worldwide. Corporate data and product information are

available at www.cyanotech.com

Safe Harbor Statement under the Private

Securities Litigation Reform Act of 1995

Except for statements of historical fact, the

statements in this press release are forward-looking. Such statements are subject to a number of

risks and uncertainties that could cause actual results to differ materially from

the statements made. These factors

include, but are not limited to, general economic conditions, forecasts of

sales in future periods, changes in sales levels to our largest customers,

weather patterns, production problems caused by contamination, risks associated

with the acceptance of new products, competition, foreign exchange

fluctuations, government regulation, and other factors more fully detailed in

the Company s recent Form 10-Q and annual form 10-K filings with the Securities

and Exchange Commission.

73-4460 Queen Kaahumanu

Highway, #102 ~ Kailua-Kona, Hawaii 96740

(808) 326-1353 fax (808) 329-3597 ~ www.cyanotech.com