This study was carried out as a survey of the species of decapod Crustacea found along the Black Sea coasts of Istanbul. It also aims to report on some of their ecological properties. Samples were collected at 36 stations during 2000 and 2001 from depths of 0.5-65 m using a scoop net, dredge, beam-trawl, or trammel net. A total of 15 species of decapod crustaceans was identified. One of these, Philocheras fasciatus (Risso, 1816), is herein reported for the first time from the Turkish coastal waters of the Black Sea. Primary hydrographic conditions such as temperature (range 8.0-21.8 degrees C), salinity (16.7-17.8 parts per thousand), and dissolved oxygen (4.5-9.0 mg/l) were recorded at each sampling occasion.