Abstract: The gas extraction radius directly affects the gas drainage rate and is the main basis for the coal seam gas pre-drilling arrangement.The existing determination methods are analyzed, and the determination method based on the gas flow rate of the borehole and the gas content of the coal seam is proposed.The effective radius of the gas extraction can be accurately determined, and the basis for determining the gas extraction radius is derived by using the regression analysis method.The field test is carried out on the 4# coal seam of Hexi coal mine, and the flow of the field extraction hole is monitored for 60 consecutive days.The verification and verification of the residual volume and pre-extraction rate are carried out to verify the gas extraction time to 180 days.At daytime, the drilling gas extraction radius is 6.5 m and the drilling distance can be set to 13 m.