According to the characteristics that indoor gas leakage is not easy to be diffused in the limited space, the effect of wind speed for the leakage diffusion of indoor gas was analyzed, and indoor gas pipeline leakage model was established. The computational fluid dynamics software was used to make numerical simulation of steady state indoor gas leakage of 2 kinds of gas, natural gas and liquefied petroleum gas. To analyze the volume fraction of the 2 kinds of indoor gas in the space at the wind speed of 1 m/s and 3 m/s, and leakage time of 10, 60, 120 s, and 240 s. The results show that the wind speed could accelerate the diffusion of the indoor gas. The leakage of liquefied petroleum gas was more likely to accumulate, and to form the hazardous area of explosion. The research results could provide theoretical basis for dealing with the gas leakage accident.