[Objective] To comprehensively assess the groundwater quality in typical arid grassland. [Method] Based on the survey of pollution sources and analysis of onsite water quality monitoring of Darhan Muminggan United Banner （Damao County） which situated in the inland river basin at the north foot of Yinshan Mountain, the Nemero index method was used to assess the groundwater quality of this area, and the causes for the pollution were also analyzed. [Result] The groundwater quality in Damao County is between poor and very poor. [Conclusion] This study laid the foun- dation for the control of groundwater pollution in Damao County.
