A child motion apparatus includes an apparatus base, a movable carrier, a seat mount, a motion mechanism, and a seat assembly. The movable carrier is movably disposed on the apparatus base along a sliding direction. The seat mount is rotatably connected to the movable carrier about a rotation axis perpendicular to the sliding direction. The motion mechanism includes a sliding mechanism and a rotating mechanism. The sliding mechanism connects the movable carrier and the apparatus base for sliding the movable carrier relative to the apparatus base along the sliding direction. The rotating mechanism is disposed on the movable carrier and connected to the seat mount for rotating the seat mount about the rotation axis. The seat assembly is detachably connected to the seat mount, so that the seat assembly slides and rotates together with the seat mount.