Abstract: In present work,the change laws of grain temperature and moisture during vertical mechanical ventilation were studied,using numerical and experimental method simultaneously,and taking a square bin in Chengdu as the experimental object.The experiment was carried out for 169.1 h continuously,and then the experimental data were compared with the simulation results.This work solved the problem that the unstable boundary condition could have an adverse effect on the accurate calculation,and verified the accuracy and feasibility of simulation using the model built,and which offered a guide for developing grain storage technology.