Abstract: A teaching playback swing-phase-controlled above-knee prosthesis comprises a thigh frame, a leg frame, an air cylinder interconnecting the thigh and leg frames and provided with adjusting means for adjusting the degree of opening the valve of the air cylinder to a plurality of degrees respectively for a plurality of walking speeds selected during trial walking, a mode selecting switch having positions respectively for setting degrees of opening of the valve of the air cylinder in a teaching mode and for a playback mode in which one of the degrees of opening is selected according to an actual walking speed, an opening detector for detecting the degree of opening of the valve of the air cylinder, an opening storage device for storing a plurality of set degrees of opening of the valve of the air cylinder, a phase detector for detecting swing phases and stance phases, walking speed detector for detecting an actual walking speed, and control unit for adjusting the degree of opening of the valve of the air cylinder