Abstract: Static storage of grain accounts for the main part of the whole grain storage cycle, and the external environmental temperature change is the main factor affecting the temperature of static grain storage. The COMSOL numerical simulation software was used to establish a 3D physical model of a large horizontal warehouse for static grain storage and further study the temperature change of paddy grain pile in the warehouse within one year under static storage, the simulated data was compared with the measured data. The results showed that the grain temperature in the warehouse changed significantly with the external environment temperature and showed the seasonal change trend; when the ambient temperature of the warehouse increased and then decreased, the grain pile produced a relatively high temperature zone, at about 1 to 3 meters away from the wall of the warehouse. In comparison with the measured results, the average temperature change of the whole grain pile within one year was basically similar. The measured value of the grain temperature was slightly higher than the simulated value, and the maximum error was 0.91 ℃. The research results can provide references for the optimal design research of the storage ventilation system.