Abstract: In order to realize the long-term flight of high altitude scientific balloon. The paper designed the renewable energy system of high-altitude scientific balloon and made the energy balance analysis. The solar irradiation model and energy balance state model are established,meanwhile,the parameters and mechanical structure were designed based on the charge-discharge balance of electric battery. Then the paper gave the laying method of solar cell based on the optimization function,the parameters of different laying methods are calculated while the advantages and problems are summarized. According to it,a new laying method which adapted to highaltitude scientific balloon is proposed. Finally,the prototype was designed and tested. This prototype is the first near-space scientific balloon circulation energy system in China which obtained a series of valuable data. The data showsed that the energy balance analysis method and multi-objective optimization function proposed in this paper have satisfactory operability while the deviation from the theoretical calculation is less than 5%. It means that they can be used as the design basis and upgrading method for subsequent projects.