This paper propose a new method to predict fatigue life based on the virtual load spectrum technology. Taking the bevel gear deceleration system as the object, the contact model of bevel gears was calculated with finite element analysis for stress and points cloud data about gear drive. According to the analysis results, the estimated fatigue life of bevel gear drive based on Miner and Corten-Dolan criteria was compared with the results of simulation cloud life.The application case demonstrates higher accuracy and reliability of fatigue life analysis results based on the virtual load spectrum calculation under the engineering application background.