Abstract:According to the field investigation in Yellow River Estuary at February May and August in 2013, the characteristics of intertidal macrozoobenthic community from 2 sections in 3 seasons, including its species, abundance, biomass, dominant species and diversity, were analyzed. The community composition and structure were analyzed, and ecological quality was also evaluated by AMBI and m-AMBI. A total of 52 macrobenthic species were collected and identified. Polychaete was the most speciose group with 24 species (46.15%), followed by Mollusca (14 species), crustacea (12 species), fish (1 species) and Nemertinea (1 species). Species number was highest in spring (38 species), and lowest in summer (16 species) (Table 1). Seasonal variations were identified for abundance and biomass. Abundance was highest in spring (3 549.33 ind/m2), much higher than in winter (256.67 ind/m2) and summer (100.67 ind/m2) (Table 3). Neverita didyma was the major contributor, accounting for 75.44% of the total abundance. Biomass also showed significant seasonal variation, highest in spring, followed by summer and then winter (Table 3). Macrophthalmus japonicus was the most important contributor to the total biomass, accounting for 49.86% across all sampling seasons. These results were also confirmed by CLUSTER and SIMPER analysis (Fig. 2). The change of community structure was caused by unstable substance near the Yellow River Estuary and seasonal variation of environmental factors such as salinity, and some kinds of human activities. The analyses of AMBI and m-AMBI showed that the ecological status here was slightly disturbed (Table 4).