XuZi net is one kind of the trap nets that are widely used in Yellow River estuary area. For the better conservation and management of fishery resources in Yellow River estuary area, the species compositions of catches with XuZi nets in spring and summer were analyzed. Based on the data obtained from three investigations into the catch composition of Yellow River estuary with XuZi nets in May 2013 and August 2014, indices of Sorensen similarity (SS), species richness (R), Shannon2-Wiener diversity (H), evenness (J) and index of relative importance (IRI) were calculated. The results showed that there were altogether 53 species in the catches of spring and summer, of which 10 were common species; the numbers of dominant species (IRI>1 000) in spring and summer were respectively 7 and 9, with 2 species in common; the Sorensen similarity coefficient between the catch compositions of spring and summer was 0.19; the indices of R, H and J of the catches were respectively 15.81, 2.91, and 0.51 in spring and 11.26, 2.17, and 0.43 in summer; and the average catch biomass and catch weight were 8766 ind/net and 55.04 kg/net in spring, and 3390 ind/net and 50.56 kg/net in summer. The results showed that the biodiversity level in spring was higher than that of summer, and in spring, the catch composition of XuZi net was complex and with a high percentage of young individuals, which would exert adverse effects on   fishery resources protection in the long run. The data provided a scientific reference for fishing gear management and sustainable fishery development in Yellow River estuary area.