Abstract: Fully mechanized working face pass abandoned roadway was difficulty technology problem that influence safety and high effective mining，then roof mechanized model during pass abandoned roadway was built，then the influence factors to roof stability were analyzed，which included main roof broken position，periodic weighting distance，main roof thickness and abandoned roadway width and so on，the results showed that it was unsafe as main roof broken line located above abandoned roadway, then the working resistance of support that pass abandoned roadway safety was put forward，the abandoned roadway width and roof stability presented as inverse ratio，the periodic weighting distance and roof stability presented as directly ratio，the influence that main roof thickness to roof stability was small.