Based on the water environmental pollution issues caused by aquaculture wastewater discharge in the Yangtze River Delta region， this study conducted a comprehensive survey on the pollution characteristics of aquaculture pond wastewater in the Yangtze River Delta Ecological Green Integrated Development Demonstration Zone （Wujiang District， Qingpu District， Jiashan County）， and evaluated the removal effects of the "three ponds and two dams" wastewater treatment system on the main pollutants， including total nitrogen （TN）， total phosphorus （TP）， and permanganate index （COD_Mn）. The results showed that the overall pollution level of aquaculture wastewater in the demonstration zone was moderate， but there were significant differences in pollutant concentrations in the aquaculture wastewater of different areas， generally showing a phenomenon of Jiashan County > Wujiang District > Qingpu District. In addition， the pollution characteristics of different species aquaculture wastewater also showed significant differences. The pollutant concentrations in the aquaculture wastewater of reptiles were the highest， with TN and COD_Mn as representative pollutants， while those of crabs were the lowest， with only partial COD_Mn exceeding the standard. The "three ponds and two dams" process had the highest removal rate for TN， with sedimentation ponds being particularly effective. Followed by COD_Mn， with sedimentation ponds and ecological ponds showing better removal effects， while the lowest removal rate for TP. Based on the above pollution characteristics of aquaculture wastewater and the pollutant removal efficiency of the "three ponds and two dams" process， the following improvements to the wastewater treatment measures are proposed: For reptiles， it is recommended to increase the volume of sedimentation ponds and ecological ponds in the "three ponds and two dams" process to specifically improve the removal efficiency of TN and COD_Mn； for fish and shrimp aquaculture wastewater with lower pollutant concentrations but greater fluctuations， maintain the existing process to ensure the standard discharge of pollutants； for crab aquaculture wastewater that occasionally exceeds the standard for COD_Mn， it is recommended to adopt a more economical sedimentation pond + filtering dam "one pond and one dam" treatment process， focusing on reducing the concentration of COD_Mn. The implementation of the above strategies is expected to promote the transformation of the aquaculture industry in the Yangtze River Delta demonstration zone towards green development and promote the continuous optimization of water environmental quality.