Abstract: In order to study the leakage and diffusion of LPG spherical tank, a three-dimensional model of spherical tank by taking a spherical tank as reference, was established based on a computational fluid dynamics software FLUENT. The danger zone after the leakage of natural gas was determined according to LPG explosion limit of 1.5%-9.5%. Simulation results showed that the leakage and diffusion laws of LPG and further the danger zone of the leakage and diffusion of LPG could be predicted based on these factors. This paper provided a reference for the prevention, control and emergency escape of similar accidents.