Abstract: To approach the interrelationships between fish community distribution characteristics and environmental factors, the widely used generalized additive model (GAM) was applied to analyze the relationships between the fish community and environment in an archipelago of East China, and to predict the distribution of the fish community. The model performed well. The richness index and diversity index of the model explained 68.9% and 64.6% of variance, respectively, and the correlation coefficient between the predicted and measured values  was 0.53. The distribution of the fish community diversity was mainly affected by habitat type, season, water temperature, and water chlorophyll and oxygen concentrations. There existed slight differences in the factors affecting richness index and diversity index. The main factors affecting the richness index were habitat type, month, water temperature, and water chlorophyll and oxygen concentrations, while the main factors affecting the diversity index were habitat type and water chlorophyll and oxygen concentrations. In the study area, the richness and diversity indices were higher in the central area than in its surrounding areas, and were higher in the sand/mud habitat and rocky habitat.