Abstract: Local geology of Dachang gold deposit was summarized simply according to detailed fieldworks and indoor researches. Based on microthermometic analyses of fluid inclusion, it was considered that metallogenic stages could be divided into poor mineralized quartz, quartz sulfide, quartz stibnite, visible-gold-bearing quartz and quartz calcite ones early and late. Poor mineralized quartz veins (metallogenic temperatures are about 350℃, and homogenization temperatures are 280~360℃), native-gold-quartz-sulfide cataclastic ores (metallogenic temperatures are about 301℃, and homogenization temperatures are 220~280℃), gold-quartz-stibnite ores (homogenization temperatures are 160~220℃), and native-gold-quartz veins (homogenization temperatures are 160~220℃), formed respectively in the former four stages, and little silicification and carbonification (homogenization temperature is lower than 160℃) could happen in the above four types of rocks or ores during the latest quartz calcite stage. Accompany with Laser Raman spectrum analyses, it was concluded that the metallogenic fluids underwent low salinity H2O-CO2-NaCl fluid system in lithostatic pressure system (metallogenic pressure is 215MPa, metallogenic depth is 8.1km) in the early stage, low salinity H2O-NaCl fluid system in lithostatic to hydrostatic pressure system (metallogenic pressures are 49~108MPa, metallogenic depths are 5.5~8.6km) in the middle stage and low salinity H2O-NaCl fluid system under hydrostatic pressure system (metallogenic pressures may be low than 40MPa) in the latest stage, respectively. Finally, the author thought the genetic type of Dachang gold deposit belongs to epizonal to mesozonal orogenic gold deposit.