Abstract: The data of the discharging amount of the main organic pollutant (N, P) to Tongan Bay from all the pollution sources: the aquaculture industry, the industry along the bay, the shipping industry, the agriculture and municipal wastewater, Dong-Xi river runoff in 2000 and 2004 years was examined to estimate the proportion of the aquaculture pollution of all the sources so as to make the aquaculturist recognize the environmental pollution degree of aquaculture really and make true evaluation. The result shows the pollutant discharging amount is 19 063.6 and 34 588.1 t in 2000 and 2004, respectively. The pollutant from the main source Dong-Xi river runoff is 8 564.8 and 21 137.3 t, account for 44.93% and 61.11%, respectively. The pollutant from the municipal wastewater is 6 552 and 9 487 t, account for 34.17% and 27.43% separately. Thirdly, the pollutant from aquaculture industry is 3 473.3 and 3 266.4 t, account for 18.22% and 9.44% separately. The pollutant from the industry along the bay is 227.6 and 482.3 t, account for 1.19% and 1.39%. The pollutant from agriculture is 239.82 and 208.6 t, account for 1.26% and 0.60%. The last one is the shipping industry, the pollutant is 6.1 and 6.5 t, account for 0.03% and 0.02% separately.According to estimation, the N and P imbibed by animals account for 14.58%, 26.3 2% and 20.91%, 37.02% of all the pollutant discharging from the aquaculture in 2000 and 2004. So the aquaculture pollution to Tongan Bay actually account for 17.37% and 8.74% in 2000 and 2004, respectively.