| Based on detailed description of the geological features of Dadonggou Pb-Zn ore deposit, the genesis and prospecting potential of the Dagonggou's Pb-Zn deposit are alalyzed. Petrography and homogenization temperatures of fluid inclusion, Laser Raman spectra of fluid inclusion, H, O, S, Pb isotopic elements, major elements, rare earth elements and SHRIMP U-Pb are tested. The component of the original mineralization fluid system is NaCl-H2O-CO2, the temperature of the original mineralization fluid ranges from 157.4℃to 312.5℃, the average salinity of fluids in the main mineralization stage is 7.77wt%, the density ranges from 0.6g/cm3 to 0.825g/cm3 and the estimated pressure is 115MPa. The average salinity of fluids in the post mineralization stage is 11.33wt%, the density ranges from 0.725g/cm3 to 0.875g/cm3 and the estimated pressure is 7～10MPa. On the whole, the fluid of the mineralization evolution from high pressure, low salinity and low density to low pressure, high salinity and high density, the mineralization depths are about 0.7～8.9km. Then, the ore-forming fluids may belong to a mixed solution between meteoric water and magmatic water. Gaseous phase are enriched in CO2 with minor amounts of H2O, N2, CH4 and H2S, so ore deposit is formed in the reduction environment.δ34S ranges from -14.3‰～9.4‰, concentrates in the range of 3.0‰～6.0‰, and sulfur come from the deep crust or upper mantle, Pb isotopic composition come from mantle with a few crust lead. Geotectonic setting is island arc system, deposit has experienced the sedimentary-exhalative mineralization and hydrothermal alteration which happened in late mineralization, so it can be classified as tansformed sedimentary-exhalative deposit. Through the analysis of SHRIMP U-Pb datas of Dadonggou and Xiaodonggou deposit, volcanic rocks which located in southwest were pushed over into southeast above on thick sediment layer, a great prospecting potential may locate in southeast.
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