Embodiments of this application provide a speed shifting apparatus, a control method thereof, a steering system, and a control method thereof, and relate to the field of mechanical transmission technologies. The speed shifting apparatus includes: an outer rotating wheel; an inner rotating wheel, where a rotation axis of the inner rotating wheel is parallel to and different from a rotation axis of the outer rotating wheel; and a plurality of meshing members, arranged along a circumferential direction of the inner rotating wheel or the outer rotating wheel. Either the outer rotating wheel or the inner rotating wheel is provided with a plurality of sliding grooves, and the plurality of sliding grooves are in a one-to-one correspondence with the plurality of meshing members.