Several scientific investigations carried out by the Institute of Oceanology, Academia Sinica during 1956-1958 on the Xisha Islands reveal that these islands harbor a rich molluscan fauna which is heretofore poorly investigated. A study of the prosobranchiate gastropoda yielded 262 species, belonging to 95 genera and 43 families. The majority of the species are tropical in nature. An analysis of the species composition of this molluscan fauna indicates that it is similar to that of its neighbouring regions, such as Malaya, Indonesia and the Philippines. It is characteristic of the tropical Indo-Malayan Subregion. Based on materials collected along the Chinese coasts during the past 20 years or more, we are able to note the limits of distribution of each species listed in this paper. Of the 262 species, 44 species [e.g., Trochus conus Gmelin, Astralium petrosum Martyn, Phalium bandatum Gmelin, Harpa nobilis R?ding and Terebra chlorata Lamarck etc.] are found only in Xisha Islands; 147 species [e.g,Haliotis asinina Linnaeus， Trochus niloticus maximus (Philippi), Lambis lambis Linnaeus etc.] are found also in Hainan Island; 194 species [e.g., Turbo petholatus Linnaeus, Lambis truncata sebae (Kiener), Chlypypraea testudinaria(Linnaeus), Charonia tritonis (Linnaeus), Mitra mitra (Linnaeus) etc.] are also reported from Taiwan Province;33 species, [e.g., Tectus pyramis (Born), Nerita costata Gmelin, Polynices pyriformis(Recluz), Cypraea vitellus Linnaeus, Oliva ispidula Linnaeus, and Conus textile Linnaeus etc.] are found also in the coastal waters of Guangdong and Guangxi Provinces ; Only 7 species viz. Scutus sinensis (Blaiville), Patella stellaeformis Reeve, Clanculus denticulatus Gray, Nerita albicilla (Linnaeus), Cerithium sinenes (Gmelin), Mauritia arabica(Linnaeus) and Drupa margariticola (Broderip) may be found as far north as Pingtan and Dongshan in Fujian Province.