Abstract: To solve the problems of support downslide and grip, rib spalling, strong deformation of safety exit and stope space occur frequently in the process of large inclined angle “three soft” unstable coal seam mining by cantilever support,this paper systemically analyzes the major issues that occur during mining production and their adverse impacts on large inclined angle “three soft” unstable coal seam based on the background of Yong’an Coal Mine in Henan Province. And then, some comprehensive measures including driving method and speed adjustment, reinforced support and innovation to the process are taken. Engineering application results show that, these measures can effectively improve circumstance of stope and safety conditions, increase production efficiency.