Abstract: Field monitoring of arsenic in the surface water and groundwater sources of both the source and upstream areas and the main tributary of the Shiquan River Basin were done to analyze the distribution and causes of arsenic in the basin. The results showed that arsenic in the basin was affected by natural factors, and was mainly affected by underground hot spring water. There is high arsenic inflow in the upper reaches of Shiquan River. It was found that the arsenic content in the water body in the upper reaches of the study area was significantly higher than that in the lower reaches of the study area The arsenic content of one tributary, named Numazhuomu Qu, was 3. 02 times higher than the standard at the section of 800 meters away when it flows into the main stream. The arsenic concen- tration of the four selected groundwater monitoring sites exceeded the standard, among which, the arsenic concen- tration of the No. 3 site in the west side of the Geji concentrated drinking water well was 2. 93 times higher than the standard limit.