Abstract: Based on field measurement of fracture development rules in large span open-off cut of thick roof and the existing problem of present supporting scheme in a certain coal mine,this paper analyses the supporting mechanism of high strength and pre-stress anchored bolt(anchored rope).Reasonable anchored bolt(anchored rope) supporting design is determined by numerical simulation and supporting experience.Industrial practice shows that this technology could control the severe deformation of soft fractured surrounding rock effectively in this large span open-off cut of thick roof,also it provides reference for similar conditions of roadway control.