中文摘要：

2006年3–5月,采用国际通用的截线样带法对海南省西沙群岛主要珊瑚礁海域的18个岛礁造礁石珊瑚进行了实地调查,共记录13科45属188种,其中62个新记录种。整合文献资料,该海域共记录造礁石珊瑚13科50属204种,基本包括分布在我国（不含台湾省）的所有造礁石珊瑚科属和绝大多数种类。造礁石珊瑚以生长速度快的分枝状珊瑚为主。物种多样性最高的是华光礁海域、金银岛海域和永兴岛海域。聚类分析可以把18个调查岛礁分成3个类群：有人类居住的大型环礁群、独立岛礁群和无人居住的大型环礁群（华光礁）。为了有效保护珍稀的造礁石珊瑚资源,按照其种类多样性和分布特点重点保护关键海域是十分必要的。

英文摘要：

Coral surveys at Xisha Islands in the South China Sea in 2006 recorded 188 species and subspe-cies in 45 genera and 13 families.Combined with literature records,a total of 204 species of scleratinian.corals in 50 genera and 13 families are known from the Xisha Islands,a list which includes almost all known species in China as well as 62 new record species.The scleratinian fauna was dominated by branching spe-cies which are generally rapidly growing corals.Various diversity indices revealed that the reefs at Huaguang,Treasure Island and Yongxing Island exhibited the highest species diversity.With increasing at-tention paid to coral reef conservation,it is desirable to establish key protected areas based on the character-istics of scleractinian species diversity and distribution.