|Abstract:The Quman Geothermal Field in Tashkorgan County, Xinjiang, is located in the north section of the Tashkurgan Tajik Autonomous County in the east central part of the Pamir Mountains. The borehole reveals a maximum temperature up to 162°C of the Quman Geothermal Field. In this paper, O, H, S and He isotopes in geothermal water and surface water samples from the Quman geothermal field have been determined. Combined with hydrologic geochemistry features such as B and Cl, the recharge source, elevation and temperature of the recharge area, heat source of geothermal field and circulation characteristic are analyzed. The test results are as follows, in the geothermal water, the value of δ18O, δ2H and δ34SCDT is -8.00‰ ~ -10.77‰, -72.50‰ ~ -82.12‰, 21.10‰ ~ 23.76‰, respectively. In the other water, the value of δ18O, δ2H and δ34SCDT is -10.50‰~-13.03‰, -81.68‰ ~ -93.87‰, 1.16‰ ~7.05‰, respectively. The value of 4He is ×10-4, and the ratio of 3He to 4He is 0.397 Ra. After analyzing the data, the conclusions are as follows: (1) The δ2H-δ18O distribution in the Quman geothermal field is below the precipitation line and extends to the upper right. The value of TDS is1～4g/L，the value of rNa/rCl is higher than 0.85，the value of the ratio of Cl to Br is higher than300.The Quman geothermal field is a circulating geothermal water, which is mainly supplied by meteoric water. The recharge area is a high mountain area on the southwest side of the geothermal field, the elevation is about 4657m, and the temperature of the recharge area in rainy season is from -3 to 2°C. (2) The ZK7 and ZK22 with higher outlet water temperature and higher thermal storage temperature in Quman geothermal field show larger ‘Oxygen-18 drift’, the δ18O drift value in the two boreholes is 2.12‰ and 2.35‰, respectively, which is supposed to belong to the magmatic heat source geothermal system. (3) The concentration of D in the geothermal water is 4‰ higher than that of the cold water, the 34S isotope shows that the geothermal water has the characteristics of deep source sulfur, the ratio of 3He to 4He has the characteristics of helium isotope composition of mixed atmospheric and crustal sources, the mass concentration of B in the geothermal water is 27 times than that in other water bodies, which indicate that the depth of geothermal water circulation is relatively deep, and there may be a small amount of primary magmatic water mixing during the deep circulation.