Remaining useful life prediction is an effective solution to solve the problem of short life and high cost of PEMFC system. In thispaper, the degradation mechanism of PEM system, including proton exchange membrane, catalytic layer, diffusion layer and other components, was reviewed. The factors influencing the aging of PEM system were summarized from intrinsic factors and external factors, especially improper operation in operation and management would accelerate the aging of PEM system. The commonly used degradation performance indexes to characterize the aging degree of PEM were summarized. The selection of degradation performance indexes is of greatsignificance to the research of life prediction. The advantages, disadvantages and applicability of different indexes were introduced. Common faults and life prediction were introduced from three aspects: model-driven, data-driven and hybrid-driven. Model-driven and datadriven have their own advantages and disadvantages. Hybrid can combine their advantages and improve the precision and accuracy of prediction. Finally, the future direction of prediction research was prospected.