Abstract: In order to solve the problem that the surface subsidence coefficient of shallow buried coal seam is difficult to determine in northern Shaanxi mining area, the data of surface rock displacement parameters in coal seam mining under different topographic conditions are collected in this paper. On the basis of analysis, three main influencing factors affecting the surface subsidence coefficient of the mining area are obtained, that is the ratio of bedrock thickness and overburden thickness JZ, the ratio of bedrock thickness and mining height JC, slope stability G. In addition to, taking JZ and JC as independent variables and combining topographic forms with piecewise function, the expression of surface subsidence coefficient is given respectively. The research results show that the surface subsidence coefficient of loess gully region should be mainly calculated by JZ, and the ratio of the height of the slope to the overall thickness of the loess cover should be considered. The JC of the ground surface subsidence coefficient should be calculated at aeolian sandy site. Through two engineering examples, the reliability of the piecewise function expression of surface subsidence coefficient with JC and JZ as independent variables is verified.