Based on the fishery resources surveys in the Xuliujing reach of the Yangtze River from December, 2005 to March, 2006, and July-September, 2006, the community structure and biodiversity of fishery resources was preliminarily analyzed. The results indicated that, in this area, there were 48 species of fishes, 3 species of shrimps, and 2 species of crabs collected, which belonged to 12 orders, 20 families, 44 genera. The index of relative importance (IRI) was used in measuring ecological dominance of species to decide the role each species played in the community. The index of relative importance (IRI) above 1000 was defined as the dominant species. Only three dominant species, Macrobrachium nipponense, Synechogobius ommaturus, Parabramis pekinensis, accounted for 32.09% of the total catch in weight. Four diversity indexes, Wilhm's index(H″), Margalef’s index(R″), Pilou’s index (E″), McNaughton’s index (D″), which were calculated by weight to analyze the characteristics of species diversity of fishery communities. The value of H″ was 3, R″ was 4. 66, E″ was 0.76 and D″ was 0.22. The fishery community type in Xuliujing reach of the Yangtze River is the overlapping type of estuary fishery community and the fresh water fishery community. Compared with other sections of Yangtze River, the diversity of fishery community in Xuliujing reach of the Yangtze River is in the medium level, while the community structure is unstable, and the community has the miniaturized tendency.