This rehabilitation device consists of a pneumatic cylinder, a footrest for placing a foot, a stopper part physically suppressing excessive bottom dorsiflexion exceeding the set angle of the footrest, a calf placed, and a frame supporting them. In addition, the angle adjuster shown in the figure is rotatable by 20 degrees. It has a structure that is useful either in a sitting posture or a supine position. In the rehabilitation operation, the direct motion movement of the cylinder is switched to the rotational motion about the ankle position, and producing a mechanism shown in Figure 3 that can train up to 20 degrees of dorsiflexion and 45 degrees of planter flexion. This angle is the joint movement range established by the Japan Rehabilitation Medical Society [21].