The process of short-wall mining with different wide coal pillars is simulated by rock failure process analysis system(RFPA2D) in this text,the influences of different wide coal pillars no the ground subsidence are analyzed and compared,the damage mechanism and movement rule of rock mass influenced by mining action are reproduced,the appropriate sizes of coal pillar are determined.It offers the basic basis to realizing the protection of laneway,the reasonable utilization of resources and the sustainable development of economy.