Renewable power system using solar array is one of the most critical subsystems for stratospheric airships. It is important of thermal protection for the stratospheric airship, because excessive temperature of solar cell may reduce its conversion efficiency and age the envelope material underlaid solar cells. Multi-objective optimization of a thermal protection structure with heat dissipation and insulation layers for solar array of a stratospheric airship is performed in this paper. The optimization process is carried out by a Nondominated Sorting Genetic Algorithm to decrease the sensitivity toward weights or demand levels. The specific temperature difference, which indicates the ratio of temperature reduction and structure density, and the output power of solar array are used to present the optimization aims. Three geometric variables related to the number of fins, width ratio of fins and thickness ratio of dissipation and insulation layer are selected as the design variables. Pareto optimal fronts representing the trade-offs between the performance parameters are obtained at last and optimization results are compared with previous studies and the thermal protection effects and output power of the solar array are both more excellent. Furthermore, the simulation of the thermal protection structure with optimization parameters are carried out at last. (C) 2018 Elsevier Ltd. All rights reserved.