Choosing COD_Mn, NH₃-N, TN and TP as the pollution indicators, we calculated the permissible pollution bearing capacity of Changhu Lake by using uniform mixture model, Dillion model and Hetianjian model. And in view of the current characteristics of the serious aquaculture pollution in Changhu Lake, we evaluated the aquaculture pollution load by the method of pollution discharge coefficient and pollution load ratio. The results indicated that the permissible pollution bearing capacity of COD_Mn, NH₃-N, TN and TP were 8 523. 15 t·a^-1, 1 495. 57 t·a^-1, 1 932. 70 t·a^-1 and 96. 64 t·a^-1, respectively; The aquaculture pollution load of COD, NH₃-N, TN and TP were 3 724. 10 t·a^-1, 279. 96 t·a^-1, 26. 42 t·a^-1 and 51. 98 t·a^-1, respectively. Aquaculture produce significant amount of COD and TP pollution to Changhu Lake and is an important pollution source of organic pollution and eutrophication.