Proximal femur fractures are the most common injury pattern in elderly. The design of proximal femur should be patient-specific to reduce contact stress and friction as well as instability, compared to commercial prosthesis. The aim of this study was to develop patient-specific design of proximal femur prosthesis of adult Indonesian female. This paper describes a way in which the customized design is based on Computer Tomographic (CT) imaging of the patient's proximal femur. Proximal femur morphometry such as Femoral Neck Length (FNL), Femoral Neck Shaft Angle (FNSA), and Medial Offset (MO) were used as consideration for the design because of these parameters were unique from one patient to another, especially for Indonesian patients. Previous study has concluded that Indonesian has smaller proximal femur morphometry as compared to Western population. The stress distribution and biomechanical properties were evaluated through finite element simulation. The result is one proximal femur design that is suitable for specific adult Indonesian female patient. The proposed custom femoral component design has some advantages compared with a conventional femoral component. (i) Optimal proximal femur morphology design based on patient's condition will bring less postoperative care. (ii) Owing to the resulting stress distribution, it can potentially reduce wear on the opposing contacting surface and the risk of early loosening might be reduced.