Abstract: Aiming at the mining problems of S2611 steep seam working face in Fengchun coal mine in Chongqing，the relationship between the factors such as coal seam inclination，support weight，working resistance and the support slipping，dumping safety coefficient is analyzed by establishing working face support instability model.The oblique arrangement of mechanized longwall mining method is put forward，and the ZJY2400/8.5/15 type hydraulic support which is suitable for the mining conditions is developed.And calculate the ZJY2400/8.5/15.5 type hydraulic support slipping，dumping safety coefficient is more than 1.On this basis，it is proposed to install antiskid device on the set collar，install tilting prevention device on support base，install side protecting plate on support set collar and caving shield，install the bottom adjustment device upside the support base，change the support frame transfer method and other technical measures to prevent the support from slipping and dumping for improving the overall stability of the working face supports.