Film capacitor is the key component of power electronic system and its reliability is highly related to the stable operation of the power equipment. However，voltage and temperature are the critical factors affecting aging of the capacitor. In this paper，the polypropylene film capacitor is taken as the object. The electrothermal stress accelerated aging test platform is set up，the life of the film capacitor is extracted under different temperatures and voltages and the Arrhenius model and exponential model are combined to study the life prediction of the film capacitor. The study results show that with the increase of temperature and voltage the life of the capacitor is reduced significantly，in which the influence of voltage on the aging of the film capacitor is more significant than that of the temperature. This study helps to further analyze the mechanism of electrothermal stress on the aging of thin film capacitor and can be used for life prediction to improve reliability of the system.