In this paper, a comparative study of total knee arthroplasty (TKA) between fixed-and mobile-bearing implants is presented. Reverse engineering techniques including finite element analysis were used to evaluate the mechanical characteristics in terms of the stress distribution. A virtually bearing load based on four different stages of gait cycle (0 o to 60 o flexion) was performed. The maximum contact pressure and contact area of tibial inserted component were evaluated. According to the results, the magnitude of maximum contact pressure in fixed-bearing implant increased significantly when compared to a mobile-bearing implant from 0 o to 60 o flexion. The contact area of mobile-bearing implant tended to decreased from 0 o to 60 o flexion of gait cycle. However, the contact area of the tibial inserted component in a mobile-bearing implant was significantly higher than those of a fixed-bearing implant. The body bearing weight had less influence on the maximum contact pressure as well as contact area in the mobile-bearing implant than fixed-bearing implant.