Abstract：This paper has analyzed the distribution, hydrogeological condition and hydrochemical characteristics of the drinking water type arseniasis in northern Yinchuan plain, and dealt with the distribution and enrichment environment of arsenic ions in groundwater. It is shown that the high arsenic groundwater is distributed in two zones in the alluvial lacustrine plain, and is mainly of unconfined water, with the buried depth of the groundwater table less than 40 m. The high arsenic groundwater is in a weakly alkaline and reducing environment, and the hydrochemical types are mainly HCO3-Na·Ca, Cl·HCO3-Na and Cl·HCO3-Na·Ca; This paper also makes a comparative study of the distribution and the environment geological features of high arsenic groundwater areas in northern China, which include Hetao plain in Inner Mongolian, Datong basin in Shanxi province, Xinjiang, and western Jilin Province.