Abstract: In view of the large deformation and failure of long-span rectangular roadway, taking the I section of pedestrian roadway at +480 m level in Zhangcun Coal Mine as an example, the mechanism of roadway deformation and failure is studied through field investigation and theoretical analysis. It is found that the engineering geological conditions are poor, the stress level of roadway surrounding rock is high, the design support form cannot adapt to the deformation requirements of surrounding rock, and the construction management is not in place, which is the main reason for the serious deformation and damage of the roadway. Combined with the deformation and failure mechanism of the roadway, the anchoring parameters of the repaired roadway are obtained by means of engineering analogy and numerical simulation，and the joint support method of “grouting + anchor net cable spray + floor anchor cable” with the core of “integral reinforcement + local reinforcement” was proposed for the roadway of section I of the +480 m horizontal pedestrian tunnel. The application shows that after 60 days of monitoring, the maximum convergence of the two sides is only 84 mm, and the maximum distance between the top and bottom panels is only 125 mm. The surrounding rock deformation is in a stable state, which ensures the normal use of the roadway.