Taking East Taihu Lake as the research object, this study systematically investigated the physicochemical properties, nutrient distribution and pollutant release characteristics of sediments in historical aquaculture areas and aquatic vegetation zones. The single–factor pollution index method and comprehensive pollution index method were adopted to evaluate sediment pollution, so as to clarify the sediment pollution and release characteristics in the historical aquaculture areas of East Taihu Lake. The results showed that there were significant differences in the physicochemical properties, nutrient contents and distribution of sediments between the historical aquaculture areas and the aquatic vegetation zones. The pH values (7.19 and 7.23, respectively) and moisture contents (65.84% and 54.31%, respectively) of surface sediments at 0–10 cm and 10–20 cm in the aquaculture areas were significantly higher than those in the aquatic vegetation zones (p < 0.05). Moreover, the pH value increased with sediment depth, while the moisture content decreased with depth. The average contents of total nitrogen (TN), total phosphorus (TP) and organic matter (OM) in surface sediments at 0–10 cm in the aquaculture areas were 1610 mg/kg, 665 mg/kg and 4.26%, respectively, which were 1.22, 1.43 and 1.51 times those in the aquatic vegetation zones, and nutrients in the aquaculture areas were mainly accumulated in the surface sediment layer.The average total nitrogen release rate in the aquaculture areas (31.63 mg·m-2·d-1) was much higher than that in the aquatic vegetation zones (-3.99 mg·m-2·d-1), showing a continuous release state, whereas no significant difference was observed in the total phosphorus release rate between the two zones. The concentrations of ammonia nitrogen and ferrous iron in pore water, as well as the release fluxes calculated by Fick"s Law, were significantly higher in the aquaculture areas than in the aquatic vegetation zones (p < 0.05). The average concentration of diffusive gradients in thin films–extractable phosphorus (DGT–P) in the aquaculture areas (0.026 mg/L) was 1.5 times that in the aquatic vegetation zones (0.017 mg/L), indicating a stronger release capacity of labile phosphorus.The sediment pollution assessment revealed that sediment pollution exhibited the characteristics of "vertical decrease and regional differentiation".The proportion of heavily polluted sites for total nitrogen (TN) in the 0–10 cm layer was 17.4%, and that for the comprehensive pollution index (FF) was 35.5%; this proportion for FF decreased to 26.1% in the 10–20 cm layer. The 20–30 cm layer was dominated by light pollution for FF (accounting for 37.4%). The pollution indices of the aquaculture areas were significantly higher than those of the aquatic vegetation zones at all depth layers, and heavily polluted sites were concentrated in the historical aquaculture areas. The results of this study can provide scientific support for the precise control of internal pollution in the aquaculture areas of East Taihu Lake.