Based on No.1101WX3 steeply inclined working face of Xinjiang Tianshun Mine in Fengfeng Group, the excavation method and support form of fully-mechanized caving mining and open-off cut in steeply inclined thick coal seam were systematically studied. The construction method of drilling from bottom to top and brushing from top to bottom in large section open-off cut of No.1101WX3 Face was studied. Based on the basic parameters of the surrounding rock of the open-off cut, the combined support form of ' anchor cable, W steel strip, double plastic net and hydraulic prop ' was determined, and the support technology of high strength, high anchorage point and high bearing structure was formed. The stability control of the surrounding rock of the roadway was realized, and a reliable support scheme was provided for the open-off cut excavation construction under the same geological conditions.