Abstract: As the largest inland freshwater lake in China and a critical ecological barrier in the Xinjiang region, Bosten Lake has faced increasing pressures from agricultural non-point source pollution and urban domestic sewage in recent decades, leading to exacerbated eutrophication and elevated salinity levels. In response, local governments have implemented pollution interception projects in recent years aimed at improving the lake's ecological environment. To systematically assess the ecological effects of pollutant interception and reduction measures in the Bohu Town area, this study focuses on the integrated wetland ecological restoration project on the western shore of Bosten Lake. We compared the dynamics of key water quality indicators before (2009–2016) and after (2017–2024) project implementation. Long-term monitoring data from nearshore sites (Sites 14 and 13) and an open-water site (Site 15) revealed that between 2009 and 2016, chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and salinity exhibited a fluctuating upward trend, influenced by sustained pollutant loading. Since the project became fully operational in 2017, a clear turning point in water quality improvement was observed: pollutant concentrations at all monitoring sites declined substantially, with more pronounced improvements nearshore than in the open lake. These findings indicate that by integrating sewage interception, flow diversion, and advanced wetland treatment, the project has effectively curbed pollutant inputs from agricultural drainage and domestic sewage, playing a significant role in mitigating eutrophication and reducing salinity in Bosten Lake. This study offers valuable practical insights for pollution control and ecological restoration in lakes within arid inland regions.