Abstract:Research of species distribution and diversity of the coral reef fishes was conducted by the method of line intercept transect,taxonomic diversity index,relative abundance and similarity index,according to the monitoring data investigated along the east and south coasts of Hainan island from 2004 to 2013.The results showed that,there were 6 orders, 32 families, 64 genera and 130 species of coral reef fishes with density of a decreasing trend from south to north approximately.And Perciformes was in the absolute dominance.Average diversity index of the family was 4.41 when the genera was 3.09,and normalization G-F was 0.30; Relative abundance of coral reef fishes of Perciformes has possessed absolute dominance.Six higher relative abundance families were Pomacentridae,Labridae,Chaetodontidae,Apogonidae,Tetraodontidae and Centriscidae; It was very similar in orders with similarity index between 0.86 to 1,when it was low as Family,Genus and Species,all of them below 0.5.There were many varieties and abundant species in the shallow reefs along the east and south coasts of Hainan Island,through the Jaccard's similarity index analysis.Length of fish body ranged 6~10 cm,followed by 0 to 5 cm,few of them 21~40 cm.This paper hopes to provide basic data and theoretical basis for protection of coral reef ecosystem and reef fishes,through the discussion of the species distribution and diversity of the coral reef fishes along the east and south coasts of Hainan Island in nearly a decade.