In this paper, the No.9 coal seam of Shouyang Kaiyuan Mining Industry of Yangmei Group is taken as the research object. Through the field measurement of borehole gas flow method, the extraction radius of cross-layer borehole is measured in the low drainage roadway of 9715 working face. Through research, the extraction time corresponding to different extraction rates at different positions of boreholes and ordinary boreholes is obtained, and the effective extraction radius of boreholes and ordinary boreholes under different extraction days is obtained. This test provides a guiding basis for Kaiyuan Company to reasonably design the extraction parameters of cross-layer drilling.