Abstract: A fatigue life prediction method for notched components was proposed based on the stress analysis using the finite element (FE) method. The method was applied to the notched shaft specimens made of the 16MnR steel. The cyclic elastic-plastic stresses and strains of the notched shaft specimens subjected to proportional and nonproportional loadings were analyzed using the FE method. An Armstrong-Frederick (A-F) type cyclic plasticity theory with the capability of describing the non-Masing behavior was implemented into the FE analysis. Both the experimental controlling paths and the actual experimental loading paths at the half lives were adopted in the FE analysis for the loading paths. A critical plane multiaxial fatigue criterion was used to predict the failure locations and the fatigue initiation lives of the notched shaft specimens, based on the FE stress-strain results. It is found that the proposed method can predict well the fatigue lives of notched components under both the proportional and nonproportional loading paths.