Abstract: Theoretical calculations of solar radiation and TRANSYS meteorological system are used for the calculation and characterization of radiation resources. Derive the radiation from the radiation of a typical day of the month for the extraterrestrial,horizontal and inclined surfaces,as well as the total monthly and annual radiation of total and direct radiation. And analyze the total,direct radiation under different percentages of insolation. Use TRANSYS to simulate the change of total and direct radiation of the horizontal and inclined surfaces outside the earth. The results of calculation and analysis show that the total annual solar radiation for the area of Ordos Darat Banner is 9916 MJ/m~2,and the total annual solar radiation for the inclined plane is 7675 MJ/m~2. There is a big difference between the horizontal and inclined plane radiation. The simulation method of this paper is also applicable to the calculation of solar radiation in any area.