In order to solve the problems of low loading efficiency and large load fluctuation of traditional thin seam shearer, taking the spiral blade of the drum as the research object, the variation law of the loading performance of the drum under different spiral lift angle was studied through discrete element simulation test. The results show these as follows When the spiral angle of the drum with a diameter of 1 200 mm is gradually increased, the loading efficiency of the drum is gradually increased from 73.31% to 76.56%. When the spiral angle reaches 18°, the optimal loading efficiency is obtained. When the spiral angle continues to increase from 18° to 30°, the loading efficiency of the drum is negatively correlated with the spiral angle. Based on the optimal spiral lifting angle, the structure of the spiral blades was optimized, and the simulation results showed that the loading efficiency of the drum was increased by 9.94% and the load fluctuation was reduced by 22.59%.