Hydrargyrum(Hg) and arsenic(As) in tap water of Chongqing University Town were detected by the X-atomic fluorescence spectrometry, and the United States Environmental Protection Agency (USEPA)-supported Health Risk Assessment Model was used for evaluating the potential health risk to surrounding residents caused by Hg and As in tap water. The results showed that the average concentration of Hg and As in tap water of this region were 0.6323μg/L and 20.1237μg/L respectively, wherein the Hg content was lower than the national Standards for Drinking Quality (GB5749-2006), but the As content exceeded its stipulated level, the annual personal risk level of health hazard caused by Hg and As by the way of drinking water were 2.840×10-8•a-l and 1.350×10-4•a-l, wherein Hg would not cause apparent harm to exposure population, while As was higher than the maximum acceptable risk level by the way of drinking water(5×10-5•a-l)recommended by the International Committee on Radiological Protection (ICRP).