Abstract: Taking 13121 upper working face of Gubeimine as the research background, through theoretical analysis of the initial and periodic breaking steps of thick and hard straight roof, the roof pre-splitting cutting scheme is proposed, and FLAC3D software is used to verify the cutting effect of thick and hard roof. The displacement law of thick and hard roof and the variation characteristics of advance supporting stress of working face before and after cutting roof are coMPared. The results show: Pre-splitting the top can effectively improve the working environment of the straight overlying hard thick roof. After cutting the top, the peak value of the advance supporting stress of the working face is reduced by 28.39%, the influence range of the advance is reduced by 37%, the step distance of roof collapse and coMPaction is shortened by 43.53%, and the position of the peak value of the advance supporting stress shifts to the deep. The pre-split cutting roof plays a positive role in themine pressure control of the straight overlaying working face with thick and hard roof, which has reference significance for the design of advanced support of working face.