Abstract: By the comprehensive detection technology including ground-geophysical，underground electromagnetic detection and roadway advanced detection and so on，the area of small coal mine broken was clearly surveyed in 9 coal seam.Considering the different conditions of roadway surrounding in the broken area caused by small mine gobs，the supporting manner combined with pre-grouting， shed supporting and bolting with high strength were employed.It was proved that the roadway surroundings after supporting could resist all kinds of ground pressure during the process of repeated mining in extra-thick coal seam.