Abstract: Xinjiang is situated in the interior of the Eurasian continent. This region is characterized by arid climatic conditions, presenting an uneven spatial and temporal distribution of water resources, as well as a scarcity of accessible water resources. Lakes constitute one of the primary means of water resource storage in Xinjiang. They play a pivotal and irreplaceable role in combating desertification within the arid region. They modulate the regional exchange and circulation of water and heat-carrying materials through complex multi-interface and multifactor physical processes occurring within the atmospheric boundary layer. Bosten Lake in Xinjiang was the target of this study. The Weather Research and Forecasting model coupled with the Community Land Model was employed to simulate local circulation patterns over the lake for a period of 92 days from June to August 2020. By meticulously analyzing the near-surface wind fields and water vapor distribution and using lake-removal experimental setups, the mechanism underlying the influence of local circulation on the evaporation of the lake surface was revealed: Because of the lake breeze, the water vapor evaporating from the lake surface moves toward the land, driven by the onshore air currents. Concurrently, the updraft at the lake breeze front causes this water vapor to disperse into the upper atmosphere. Under the combined forces of the valley wind and background wind, the lake breeze circulation drives the water vapor downward, accumulating it along the lakeshore to form discretely scattered water vapor accumulation zones. The specific humidity within these areas persists at an elevated level. The water vapor accumulation area of Bosten Lake is predominantly distributed on the western flank of the lake. Notably, the boundary layer height in these regions is lower than that in the neighboring land surfaces, and the underlying surface is largely blanketed by vegetation.