Abstract: Horizontal stress is one of the important factors affecting the roadway stability.Based on the actual conditions of surrounding rock in the working face 347 in Hebi mine No.2,the influence of the plastic areas and the displacement distributions around the roadway were analyzed under different horizontal stress by flac3D,which were supported with U36 steel stents.The results showed that the deformation of the roadway's sides was smaller,and the deformation of the roadway's shoulder was serious,and the floor heave was more serious with the lateral pressure coefficient increasing.So the control effect for the roadway's sides was better with the U36-steel support stents,but the shoulder and the floor were the weak parts,which need to be strengthened.