In May 2013 (spring) and October 2013 (autumn), fishery resources were surveyed using a stern-trawling shrimp net in the Oujiang Estuary area of Wenzhou. A total of 12 stations were established. The survey data were standardized according to the swept area and escape coefficient at each station. Using the methods of relative importance index(IRI), hierarchical clustering(CLUSTER), non-metric multidimensional scaling(NMDS), ABC curve, etc., the community structure, spatial distribution and stability of shrimps and crabs in the waters of Oujiang Estuary were analyzed. The aim is to study the differences in the community structure of the spring and autumn of the Oujiang Estuary. The results showed that:The two surveys identified 25 species of shrimps and crabs, belonging to 11 families and 16 genera, 18 species in spring and 23 species in autumn; The number of species in the estuary area was lower in spring and autumn, and the nearshore and island reef areas were higher; There are three dominant species of Parapenaeopsis hardwickii, Acete schinensis, and Portunus trituberculatus in spring,and five dominant species of Exopalaemon carinicauda, Solenocera crassicornis, Portunus trituberculatus, Charybdis japonica and Scylla serrata in autumn. The ecological types show that shrimps and crabs are dominated by wide temperature, low salinity and wide temperature and wide salt species, and no cold water species were found. Cluster analysis divided the stations in spring and autumn into three communities. Non-metric multidimensional scaling (NMDS) shows that the clustering results in the spring and autumn are credible (0.05 ≤ Stress<0.1).The analysis of similarity (ANOSIM) showed that the differences between the communities in spring and autumn were significant and the significance levels were less than 0.05, and the results were acceptable. The analysis of SIMPER shows that the differences between the communities in spring and autumn are mainly determined by the difference of dominant species. The results of ABC curve analysis were in accordance with the actual conditions in spring and autumn. In spring, W<0,the community composition was dominated by small, low-quality species; In the autumn, W>0, the community composition was dominated by adults.