<p>Human foot has complex three dimensions structure such as 26 bones, ligaments, muscles, skin and so on. This structure changes mechanical characteristic according to different environments and conditions. However, the mechanism is not totally understood. In the past, the gait simulator has be developed for observing changing of the characteristic. In these gait simulator, the tibia of cadaver foot are fixed and it's tendons were pulled. The cadaver foot also be impressed to ground and measured the ground reaction force during walking. In this study, we develop a bipedal robot for gait simulator that can walk and reproduce the ground reaction force of cadaver foot. It has three characteristics. (1)The foot part of separated leg can be observed in x-ray fluoroscopic system. (2)The gait simulator can attach various foot. (3)The gait simulator can walking.</p>