One of the critical problems associated with total hip replacement is the loosening of femoral stem. A major cause of femoral stem loosening is believed to be stress shielding of the proximal femur following implantation. In order to ensure the long-term success of total hip replacement, minimization of stress shielding is desirable. Since currently available femoral prostheses vary markedly in both geometry and material properties, the tendency for a particular prosthesis to result in stress shielding is not immediately obvious. A three-dimensional finite element method for calculating the magnitude of stress shielding in the proximal femur following implantation is described in this study. The computational method for quantifying stress shielding is the first method which allows direct comparison of the stress state produced by different prosthetic designs. By using this method, it may be possible to assess the long term performance of a prosthetic design prior to implantation. This method will also be helpful for performing comparative analysis for different prosthetic designs and for selecting the most suitable prosthesis for the patient undergoing total hip replacement.