The traction system is the most crucial part of an elevator. A malfunction of the traction system can pose significant safety risks to the elevator. This paper proposes a life prediction model method based on the Wiener degradation process to predict the remaining useful life of the elevator traction system. Firstly, the common failure modes of the elevator traction system are analyzed. The analysis results show that the failure form of the elevator traction system is insufficient traction force, which is manifested as wire rope slippage, reduced load-carrying capacity, etc. The fundamental cause is the reduction of the equivalent friction coefficient. Then, the traction wire rope is modeled, and the relative slip amount of the wire rope with respect to the traction wheel is selected as the characteristic parameter. The models of the relative slip amount of the wire rope under two working conditions, namely, empty-load up are calculated. Combined with the empty-load operation condition of the elevator, the failure threshold of the relative slip amount of the wire rope is calculated. Subsequently, the Wiener process degradation model in the random process method is adopted to describe the degradation process of the elevator traction system, and the Wiener process model is established. Finally, the life prediction model is used to predict the remaining useful life of the elevator. Compared with the traditional prediction methods, it can obtain the remaining useful life at the corresponding moment starting from any sample point.