Abstract: 3D-model was created with auto-distinguished boundary of human femur from CT images by using reverse engineering method to understand the effect of the mechanical properties during the procedure of human femur gait and natural frequency of human femur on arthroplasty. The finite element analysis and calculation were performed to obtain the mechanical properties corresponding to the different moment of the gait cycle, and this work was focused on the vibration analysis of human femur. A new viewpoint is presented to explain the loosening mechanism of prostheses after implantation. It is revealed that the prostheses design should consider not only the material biocompatibilities and prostheses fixation style, but also the natural frequency of prostheses to avoiding the occurrence of resonance. The conclusion is helpful to guide the selection of the material and design of the prostheses.