Objectives: The Shangxu gold deposit in Shuanghu county of Tibet is located in the middle segment of Bangong Co—Nujiang suture belt. Ore bodies controlled by the nearly EW—NWW fractures occur as veins and lens in the Lower—Middle Jurassic Mugagangri Group which is mainly composed of metamorphic flysh, quartz veins type ore and altered rock type ore coexist. Methods: On the basis of detailed geological fieldwork, we selected quart veins in different mineralization stages for the study of fluid inclusion including petrographic characteristic observation, micro temperature measurement, composition analysis and the test of the hydrogen and oxygen isotope. Results: Fluid inclusion studies show that the temperature of the fluid in main mineralization stages ranges from 195 to 230°C, the salinity from 2 to 9 wt% NaCl equiv and the density from 0.88 to 0.95 g/cm3.The content of gas phase primarily contains H2O, CO2 and N2 with a small amount of CH4, and the liquid part mainly contains Ca2+, Na+, Cl-. The oreforming fluid of the Shangxu gold deposit belongs to CaCl2—NaCl—H2O fluid system with content of CO2, low to moderate homogenization temperature, low salinity and low density, which are similar to those of typical orogenic gold deposits. According to the hydrogen and oxygen isotope test, the δDH2O, V-SMOWvalues of fluid inclusions in auriferous quartz veins range from -104‰ to -136‰, and δ18OH2O, V-SMOW from 4.92‰to 7.82‰, indicating a mixture of metamorphic water and meteoric water.  Conclusions: The Shangxu gold deposit may be an orogenic gold deposit formed under continental collisional background, and decompression caused by the migration of fluid from closed to open system is the main mechanism for the depositing of gold.