Abstract: The spent fuel dry storage facility named QM-400 module for Third Qinshan Nuclear Power Co. Ltd. (TQNPC) is the first commercial dry storage facility in operation in China. The heat transfer in QM-400 mainly consists of natural convention, conduction, conjugate heat transfer and radiation, etc. The decay heat of each fuel basket was calculated accurately at typical surrounding temperature. Mesh sensitivity analysis was performed using commercial computational fluid dynamics (CFD) code FLUENT 14.0. A set of CFD simulation models on natural convection of QM-400 were developed. The results show that the distributions of the pressure and temperature on the cylinder surface meet the rules of natural convection. Good agreements are achieved between the simulated temperature and the measured temperature at the measured points and the simulated temperature trend varying with surrounding temperature agree well with the measured trend, which demonstrates the correctness of the calculation method of natural convection in this paper. This work can be the reference of the further CFD simulation on temperature distributions of dry storage facility without thermal insulation panels.