A wrist includes a wrist housing including a wrist driving structural portion to which rotation is transmitted from a wrist driving pulley, a cylindrical portion arranged coaxially with a rotational axis of the wrist driving structural portion and penetrated by a first hand driving shaft to which rotation is transmitted from a hand driving pulley, a cable introducing portion forming an annular gap with the cylindrical portion, and a hand-driving-shaft penetrating portion penetrated by a second hand driving shaft rotating a hand interface by rotation of the first hand driving shaft being transmitted thereto, and a cable, which comes out of a second arm from a wrist supporting portion, is drawn into the wrist housing from the annular gap and is routed to a hand interface supporting portion in a slackened state.