Abstract: Eighty shallow groundwater samples were collected from the Tacheng Basin and analyzed for chemical compositions to investigate the nitrogen pollution in groundwater in the basin. The results indicate that the shallow groundwater in the Tacheng Basin is significantly polluted by nitrate. 8.8% of the groundwater samples have concentrations of NO3-N exceeding the drinking water standard, and the rate is 1.3% for NO2-N and NH4-N. The points with nitrogen exceeding the standard mainly occur in the alluvial plain of the middle and lower reaches along the groundwater flow direction. Heavy nitrogen pollution sites mainly exist near the cities of Tacheng and Yin and their surrounding areas. The occurrence of nitrogen-polluted points are adjacent to the sewage treatment plants, landfill sites and other major pollution sources. In the process of urbanization, the irrational discharge of domestic sewage is the main source of nitrogen pollution in the Tacheng basin, and the infiltration of sewage is an important way to cause nitrogen pollution in the groundwater in the study area. Redox conditions, pH, rock types of the aerated zone and conditions of filling and discharging are the main factors affecting the transport and transformation of nitrogen pollution in the groundwater.