Abstract: According to the phenomenon of rear axle housing for some kind of mining dump truck appeared cracks in the same position in the Shenhua Beidian She ngli Energy Co., Ltd. Surface Mine, the fatigue life of the rear axle housing used in this case was predicted based on dynamic stress measured from actual field conditio n of surface mine and using the assumption of the Miner linear hypothesis of damage accumulation in this paper. The rain- flow counting method to convert the rear axl e pressure signal into a rain- flow matrix was applied, so that the fatigue life of the test points could be predicted. The paper also analyzed the failure reason of the mini ng dump truck rear axle housing with finite element analysis. The article concluded that the major reasons of the failure were eccentricity between inner circle and excir cle of the truck0s rear axle housing cross profile, roadDs incline, and the unbalanced dynamic load.