Abstract: Aiming at the optimized problem of steep thick seam along strike longwall fully-mechanized caving mining process parameters of Baojishan Mine, by PFC^2D numerical simulation and on-site industrial test, the paper analyzed the influence of different caving mode and caving step distance on coal gangue flow pattern and top coal loss characteristics. The "two cuttings and one caving" interval caving coal between two cutting method can enhance the top coal caving, effectively control the content of gangue, and improve recovery rate of top coal.