In mountainous area, spatial interpolation is the traditional method to calculate air temperature by use of observed temperature data. Due to lack of sufficient observation data in mountainous areas many precise interpolation methods could give only coarse result which could not meet the demand of precision agriculture and local climate exploration. Based on DEMs of 25 m resolution, a reversed model is constructed, with which temperature is simu-lated to the corresponding slope unit from the solar radiation. Taking Yaoxian county as a test area, and mean monthly temperature data as basic information sources, which are collected from 15 weather stations around Yaoxian county in Shaanxi province from the year of 1970 to 2000, a simulation for the solar radiation cell by cell is completed. By simulating solar radia-tion at each slope and flat cell unit, the terrain revised temperature model could be realized. A comparison between the simulated temperature and the radiation temperature from TM6 thermal infrared image shows that the terrain improved model gets a finer temperature dis-tribution at local level. The accuracy of simulated temperature in mountainous area is higher than it is in flat area.