In order to explore and obtain the migration and fracture development law of the composite roof composed of coal and oil shale, the empirical formula is used to calculate the height of the caving rock zone and the fracture development zone, and the UDEC mathematical calculation model is established by referring to the mechanical properties of the overlying strata. The UDEC mathematical calculation model simulates the caving and movement of the upper bearing strata during the advancing process of the coal mining face. Get some results of the following conclusions; during the movement of the coal mining face, the rock roof formed by the coal and the oil shale above falls to the coal mining area, forming the caving rock zone in the coal mining area. The basic rock layer of the upper layer is relatively strong, and periodic fracture occurs with the advancement of the coal face.