Bainite/martensite (B/M) multiphase bearing steel has become a research focus owing to its superior combination of strength and toughness compared with conventional martensite bearing steel. Our previous study confirmed the significantly improved toughness and fatigue properties of B/M bearing steel and demonstrated that rare-earth (RE) element incorporation can enhance its overall mechanical properties, highlighting the promising application potential of RE-incorporated B/M bearing steel. However, reports on the tribological properties of B/M bearing steel remain limited. Therefore, it is necessary to investigate the friction and wear behavior of B/M bearing steel and the effect of the RE element on the behavior. In this study, oil-lubrication sliding wear tests were conducted to evaluate the friction and wear behavior of B/M bearing steel and the effects of RE element incorporation. After the wear tests, the surface morphology and microstructural evolution beneath the wear tracks of the B/M bearing steels with and without RE elements were comprehensively characterized and analyzed using contact profilometry, a white-light interferometer, SEM, TEM, EBSD, transmission Kikuchi diffraction, and XPS. The results indicated that RE element incorporation significantly enhanced the wear resistance of B/M bearing steel, reducing material loss by >25% and achieving performance comparable to that of conventional martensite bearing steel. During the initial 20 min of the sliding wear test, B/M bearing steel with and without RE elements exhibited abrasive wear. The presence of smaller martensite/austenite blocks and a reduced fraction of retained-austenite transformation in the RE-containing steel inhibited microstructural evolution beneath the wear surface, reduced the generation of large wear debris, and decreased the debris-induced stress and plowing-induced wear volume, improving wear resistance. When the sliding duration was extended to 1 h, the primary wear mechanism for B/M bearing steel with and without RE elements transitioned to oxidative wear. RE element incorporation facilitated the formation of hard Fe₃O₄ oxide films with strong adhesion to the matrix, resulting in the excellent resistance of the RE-containing steel to oxidative wear.