To more accurately simulate the local wind field caused by the terrain thermal of mountains, the atmospheric flow field of a valley industrial park was simulated by using the mesoscale weather model WRF (weather research and forecasting model) proposed by the United States NCAR (National Center for Atmospheric Research), and the simulated result was amended in a small scale (with a grid distance of 0.1 km ) by using the diagnostic wind field model CALMET. In the simulation, a triple-nested grid program is used in the WRF model, and the distance between two grids in the inner layer of the network is 1.0 km. The research result shows that there is a great difference between WRF-based simulated results and measured values, while WRF/CALMET-based simulated results are close to the measured values. The conclusion is that the WRF/CALMET coupled model should be used to simulate the atmospheric flow field of mountain regions.