The cementless prostheses used in the total hip replacement (THR) have been predominantly developed in Western countries. Although many cementless prostheses developed in Western have been applied to THR of Japanese osteoarthrosis (OA) patients, they have not been always fitted to shape of Japanese OA femurs. Because they have been designed for the primary OA which is general in Western but not the secondary OA. There are many cases of the secondary OA which has large deformation of femoral head caused of longterm subluxation in Japan. Unfitted prosthesis design gives a worse influence on its stability and stress distribution in proximal femur, and then it can cause serious stress-shielding. To develop the prosthesis suitable for Japanese OA, it is important to consider their characteristic shape of proximal femur. In this study, 3-dimensional models of proximal femur with the secondary OA were constructed by using CAD based on computed topographic (CT) images, and canal shapes of the femurs were geometrically classified by comparing these models. The cementless prosthetic stems were designed due to the classification. Furthermore, finite-element analyses were carried out for the OA femurs with the fitted or unfitted stem. Effectiveness of the prosthetic stem designs is discussed from the result.