Abstract: Low permeability coal seam,soft coal,hard extraction and low extraction rate are the main problems of gas extraction in Wuyang coal mine.According to the coupling mechanism of coal and gas and the gas migration law,through deeply analyzing Wuyang coal mine gas extraction system,using RFPA^2D-Flow to establish the pre-drainage boreholes numerical model in mining coal seam,the paper comparatively analyzes the impact of parallel boreholes pre-drainage time,boreholes spacing and suction pressure of drainage system on gas extraction effect during the process of draining gas before mining in mining gateway,and then determines the appropriate parameters of gas extraction,which improves the extraction rate of gas.