Abstract: Pressure at the bottom of bulk grain pile of a large warehouse model was simulated by PFC (particle flow code, 3D) of discrete element method, and was compared with the test results and standard value to investigate the pressure distribution at the bottom of the grain pile, including vertical pressure, horizontal pressure, vertical friction and so on, and also study the relationship between the bottom vertical pressure of the grain pile and the pile height. Results showed that PFC (3D) could simulate the nonuniformity of the bottom pressure of the grain pile well; the bottom vertical pressure was small and uniform when the pile height was low, but increased gradually and became nonuniform with the increase of the pile height; the pressure at any point of the bottom of the grain pile was related to the friction of wall of the warehouse, the internal friction of the grain pile, and the horizontal distance between the point and the two side walls which were perpendicularly intersected with each other; the nonuniform degree of the bottom vertical pressure increased with the increase of the pile height; the vertical pressure at each point at the bottom of the grain pile changed at different rates with the pile height; and the vertical pressure had a nonlinear relationship with the pile height when the pile height was large, and increased slowly with the pile height.