Abstract: Through taking the mining face of Ji₁₄-31010 protective seam in the Twelve Coal Mine of Pingdingshan Tian'an Coal Industry Co., Ltd as a test prototype, it made numerical simulation experiments, and analyzed the effects of mining height, seam spacing, interlaminar lithology on underlying coal-rock relief. By comparing the calculation results of protective seam mining heights which included 0.65 m, 1.3 m and 2.6 m, it obtained that the bigger the mining height was, the better the pressure relief effect for the protected seam was. By comparative calculation for seam spacing of 9.1 m and 29.1 m, it attained that the relief effect of protective seam became worse and worse with the increase of the seam spacing. By comparative calculation for different interlaminar lithology, it obtained that pressure relief protective effect for the protected seam below would be affected by the presence of interlaminar hard rock.