Abstract: Concerning the various usage of the stratospheric platform,a study of the solar power system of the stratospheric airship was performed.The model of the solar radiation on the airship surface was developed,including direct radiation,scattered radiation and reflected radiation.With this model,the distribution of solar energy on the solar cell array of a typical stratospheric airship was calculated.The results show that the available solar energy varies obviously with the season,latitude,area of the solar energy cell array and the airship orientation,and reaches at its maximum value at the orientations where the back of the airship is toward the sun rays.