Abstract: This study was designed to determine the effects of stocking density (0(D0), 40 ind/m3 (D1), 50 ind/m3 (D2), 60 ind/m3 (D3), 70 ind/m3 (D4)) on growth performance of yellow catfish (Pelteobagrus fulvidraco) and water quality in surrounding water of the enclosure ecosystem.The rearing trial lasted 24 days and the water quality was monitored every 3 days. At the end of the experiment, the growth performance of yellow catfish in each treatment were assessed to determine the optimum stocking density. The results showed that the final body weight,weight gain and specific growth rate of yellow catfish decreased with the increasing of stocking density, and the significant difference were found among group D1, D2 and D3 (P＜0.05). The condition factor in D1 and D2 was significantly bigger than it in D3 and D4 (P＜0.05). The nitrite nitrogen in surrounding water (p＜0.05) was significantly affected by the stocking density, and the levels of nitrite nitrogen increased with the increasing of stocking density. While the total nitrogen and nitrateSnitrogen were not affected by the stocking density (P＞0.05). During the first 18 days, the contents of ammonia nitrogen in all groups were stable at a low level and then increased significantly until the end of the experiment. Total phosphorus and phosphate showed were also not affected by the stocking density and their levels fluctuated within a certain range during the experiment period. Increase in stocking density would reduce the growth rate of yellow catfish and increase the harmful substances in surrounding water which could accelerate the deterioration of water quality.