Abstract: Due to equipment,mining process and historical reasons,the room and pillar mining had been more widely adopted in Shendong mining area.The process of extraction rate is low,left a large amount of coal pillar.Violent pressure,toxic and harmful gases occurred under gob left by room and pillar mining,which seriously affected the mining safety.Given this,the mechanism of formation is expounded and can be summarized into three stages:the room pillar happened disintegrating failure influenced by second mining coal,roof cracks and bending down,damage fracture of lower slice full-mechanized mining face extended to the whole rock formations.The cyclotron fracture of overlying pillar residue and periodic roof pressure of lower slice full-mechanized mining face are superimposed,forming a dynamic load pressure.Three points are mainly talked about the technical solution of safe driving and extraction:reasonable decorate working face location,using microseismic monitoring technology,mine pressure monitoring,surface crack and subsidence observation,the engineering measures are mainly residual pillar surface pre-splitting blasting technology and goaf filling.