Abstract: In China's various types coal mine accidents, roof accident has been high in frequency and total number of deaths, and roof accident is still a great hidden danger in safe production, each of which brings heavy casualties and great economic losses. Through the investigation and analysis, the paper summerizes 24 kinds of main factors in roof accident from the perspective of system engineering, analyzes the causing factors of roof accident with ISM method, figures out the direct and indirect relationship of these factors, establishes interpretative structural modeling(ISM), identifies the key factors and puts forward some suggestions for fundamental problems.