This paper dealt with the fatigue life of cylindrical roller bearings with several significant error sources that may occur during installations. A four degree-of-freedom quasi-static model for cylindrical roller bearings was developed, which took into account potential error sources such as angular misalignment, axial offset, and radial clearance, together with inertial loading by rotational speed and induced moment loads. A 3D contact model was employed to provide contact pressure distributions in rolling elements. The fatigue life of a cylindrical roller bearing was analyzed as a function of angular misalignment under various loading conditions. Then, the fatigue life analysis was extended to the combined effects of radial clearance, axial offset, and the number of rollers, along with angular misalignment. The computational results showed the significance of each error source on fatigue life. They further showed that cylindrical roller bearing fatigue life maximized when the radial clearances were slightly negative, and that it increased almost linearly with the number of rollers.