Skidding from the rear bearing of main shaft takes up a large proportion in the bearing failure of the aeroengine,bearing skidding could not only affects the bearing life,but also directly relate to the safe operation of the aeroengine.For better understanding the mechanism of rear bearing skidding damage,investigations were performed by utilizing of focused ion beamscanning electron microscope (FIBSEM),field emission scanning electron microscope (FESEM),energydispersive Xray spectroscopy (EDX) and surface profilometry.Analysis results show that skidding damage in the inner ring raceway and roller surface may be the result of adhesive wear and oxidation wear,moreover,there is abrasive wear between the interface of the inner ring and roller.In addition,abrasive wear occurs to the interface of cage because of the polluted lubricating oil.