In order to solve the problems of complex geology and lack of accurate basis for supporting design of M4-5 coal seam in the second mining area of Tunbao Coal Mine, a systematic geological mechanics test was carried out in view of the current situation of fault development, dense joint fissures and poor stability of surrounding rock in this area. Two measuring points were set up in the upper and lower roadway of No.WII02040503 Face by means of borehole peeping, in-situ strength test and hydraulic fracturing method, so as to obtain the core parameters of surrounding rock structure, rock mass strength and in-situ stress field. The test showed that the surrounding rock of the roadway was partially broken and the strength of the coal body was low. The ground stress field was σV＞σH＞σh type medium stress area, and the maximum horizontal principal stress direction was N55° -65°E, which was easy to cause the risk of rib spalling, floor heave and roof subsidence. Based on the test results, a targeted support scheme was proposed. Through the measures of high-strength bolt encryption, long anchor cable anchoring, advanced grouting in fault zone and closed support of floor, the deformation of surrounding rock could be effectively controlled, which provided guarantee for the construction safety of roadway to be excavated, and also provided technical reference for mines with similar complex geological conditions.