Abstract: In order to understand the change of macrobenthic community structure in Jiulongjiang Estuary in Fujian, four seasonal investigations on the macrobenthos were carried out in the mangrove wetland of Haimen Island from November 2014 to August 2015. Based on the data of species compositions, the macrobenthic community structures were studied with methods of univariate variable analysis, Cluster analysis, MDS analysis and abundance and biomass curves (ABC). The results showed that 112 macrobenthic species were identified and the annual biomass and abundance of macrobenthos were 77.58 g/m² and 991.0 ind/m², respectively. Univariate variable analysis showed that Shannon Wiener diversity index (H′), species richness index (d) and evenness indices (J′) were 2.42, 5.02 and 0.70, respectively. Among them, the biodiversity index and the evenness index were the lowest in spring, which likely due to the peak of reproduction in spring.ABC curves revealed that the communities on 1/3 of the sampling stations suffered moderate to severe degree of disturbance, which occurred mostly in spring. The fisherman activities on the mudflat in spring might have caused the disturbances. Cluster and MDS analysis showed that 6 groups can be formed at 50% similarity level with significant differences among the groups. Combined with the historical data, the community succession of macrobenthic communities was found to have varied with the environmental quality and the species had become miniaturized. Environmental factors had a great correlation with the characteristics of community distribution and water temperature, salinity and organic matter content could best explain the spatial distribution of community abundance and biomass.