Abstract: With mining depth increasing continuously in our country, in condition of mining in the deep-lying, there are many problems in determining displacement angle of stratum at present. Under the determination geology mining conditions, based on analyzing problem of displacement angle of stratum mining in deep-lying conditions at present, the determination its method is proposed, and its relationship of the run and inclination of coal layer is studied. At last, the reasonable of determination on displacement angle of stratum is verified with example, and theory basis is provided for designing coal pillar.