A motion assisting apparatus includes a multijoint structure having links in series rotatably connected in a relative manner, the links being integrally deformed in a bendable manner, a linear member inserted through each of the links, wherein one end is fixed to the link in front and another end is elongated via the link in rear, a sliding/holding part which fixes an elongated portion of the linear member, and slidably guides the rear link in a connecting direction between each of the links, a drive unit which drives the rear link to slide toward the sliding/holding part and causes the multijoint structure, through which the linear member has been inserted, to engage in an extending or flexing motion, and a control unit which drive-controls the drive unit so that a sliding direction, a sliding speed and a sliding position of the rear link will become an intended state.