In order to solve the problems of serious roof deformation and support difficulties in the extra-thick coal seam, the deformation factors and characteristics of the extra-thick coal seam’s mining roadway were obtained through field observation and theoretical analysis. The Flac3D numerical simulation software was used to analyze the original support and high-strength constant Deformation of the surrounding rock of the roadway under two kinds of roadway protection methods with the combined support of anchor, mesh and cable under pressure and pressure. The results of the study show that the roadway in extra-thick coal seams with weak interlayers has short self-stabilization time, fast deformation speed, severe roof fracture, large plastic zone damage range, and obvious overall deformation of the roadway roof; high-strength constant-resistance pressure bolt-mesh-cable support system It can adapt to the characteristics of high stress of surrounding rock, curb excessive roof deformation and damage, and meet the trend of large deformation of roadway roof under the geological conditions. Engineering practice shows that the maximum subsidence of the roadway roof is 206mm when the high-strength constant-resistance allows the anchor-net-cable support, and there is no failure of anchor rods (cables) on site. The supporting structure can meet the deformation characteristics of the roadway roof and ensure comprehensive Safe and efficient production of the working face. The research results can provide references for roadway roof control under similar conditions.