Abstract: The reservoir pore structure of He 8 member in Lian 102 well block in the south area of Sulige gas field is complex and the law of gas-water seepage is unclear.Therefore, this paper analyzes the reservoir pore structure in the study area by using cast thin section, image pore, scanning electron microscope and high-pressure mercury injection, and studies the characteristics of gas-water seepage in the process of reservoir formation by using gas-water phase permeability and visual seepage experiments.The results show that the pores of He 8 reservoir in the study area are mainly rock debris dissolved pores, followed by intergranular pores, intergranular pores and intergranular dissolved pores less developed, and the throat types are mainly flaky throat and curved flaky throat, with an average throat radius of 0.3 μm.According to porosity, permeability, displacement pressure and maximum mercury saturation, the pore structure of He 8 reservoir in the study area is divided into three types.From class I to class III, the pore combination types are intergranular pore dissolved pore, intergranular pore dissolved pore and dissolved pore intergranular pore respectively.The distribution of pore throat radius changes from single peak type or left high right low bimodal type to left low right high bimodal type, and the radius of mainstream throat gradually decreases.The physical property of the reservoir changes from good to bad, and the pore connectivity also gradually becomes worse.The types of gas drive water in the target layer in the study area are divided into three types: uniform displacement, mesh displacement and finger displacement.For reservoirs with different types of gas drive water, there are great differences in gas-water two-phase seepage, irreducible water saturation and two-phase seepage area width.The characteristics of gas water seepage are closely related to physical properties and pore structure.From class I to class III gas drive water, it changes from uniform displacement to mesh displacement, and then to finger displacement.The two-phase permeability area changes from wide to narrow, and the isopermeability point changes from high to low, the irreducible water saturation gradually increases, and the seepage capacity changes from strong to weak.Based on the reservoir seepage law, the favorable development area in the study area is predicted to provide a basis for exploration and development in the study area.