A physiotherapeutic apparatus includes a bed, a sliding mechanism, and a connecting rod combination; the bed has thereon a threaded rod, an actuating device for causing rotation of the threaded rod, and a circuit controller for controlling motion of the actuating device; the bed has two lateral rails, and a lengthways-extending rail, which are parallel to the threaded rod; the sliding mechanism has rolling wheels thereon, which fit in and roll along each one of the rails for increasing motion smoothness and steadiness, preventing tilting and reducing wear; a threaded sleeve is secured to the sliding mechanism and positioned around the threaded rod so that rotation of the threaded rod will cause forward and backward motion of the sliding mechanism; the connecting rod combination is foldable and used to fix a user's lower limbs, and it is pivoted to the bed and the sliding mechanism two ends thereof.