Jiangdongwan Au-Sb deposit is an important deposit of the Au-Sb-As metallogenic belt of Jiangdongwan in Western Hunan. On the basis of detailed petrographical study this paper mainly studies the microthermometry of fluid inclusions in quartz this deposit. The results showed that the fluid inclusions in quartz mainly are gas-liquid two phase inclusions. The ore-forming temperature is 163-290 ℃

salinity of inclusions is 1.73%-15.3%

belong to the fluid system of middle to low temperature and middle to low salinity. The fluid density is 0.81-1.01 g/cm3

the pressure lies between 13-40 MPa

the mineralization depth is 0.5-1.4 km. The homogenization temperature of the fluid inclusion have two main distribution ranges

respectively for 180-240 ℃ and 250-280 ℃

indicate the mineralization has many stages. The studies of fluid inclusions in quartz indicate that the formation mechanism of deposit mainly is fluid mixing.