The space thermal environment seriously affects the failure rate of aerospace electronic components. Aiming at the calculation of this important reliability index, a analysis method based on fuzzy logic is proposed in this paper.The method analyzes the influence of the temperature, stress and the relative change rate of the temperature and deformation on the failure rate, and effectively solves the problems of the transition from the qualitative analysis to the quantitative calculation and the missing of the traditional mathematical model. It provides an effective basis for the reliability analysis of space satellite electronic components.