A cleaner comprising: a main body that is configured to generate suction force; a suction assembly that is configured to receive and guide dust to the main body; and a coupling hose that couples the suction assembly to the main body, wherein the main body includes: an air suctioning device that is configured to generate suction force, a case that includes an interior space accommodating the air suctioning device, a driving motor that is coupled to a first surface of the case and that is configured to generate driving force, a traveling wheel that is coupled to the first surface of the case and that is configured to rotate based on driving force generated by the driving motor, a motor cover that is configured to cover the driving motor such that the driving motor is located in a space between the first surface of the case and the motor cover, a rotating shaft that is coupled to the driving motor and that is configured to transfer driving force generated by the driving motor to the traveling wheel, and a coupling unit that couples the rotating shaft to the traveling wheel, characterized in that the coupling unit includes: a rotating plate that includes a hub that is coupled to the rotating shaft, and a plurality of wheel-coupling bosses that protrude from the rotating plate toward the traveling wheel and that are symmetrically arranged about the hub. a main body that is configured to generate suction force; a suction assembly that is configured to receive and guide dust to the main body; and a coupling hose that couples the suction assembly to the main body, wherein the main body includes: an air suctioning device that is configured to generate suction force, a case that includes an interior space accommodating the air suctioning device, a driving motor that is coupled to a first surface of the case and that is configured to generate driving force, a traveling wheel that is coupled to the first surface of the case and that is configured to rotate based on driving force generated by the driving motor, a motor cover that is configured to cover the driving motor such that the driving motor is located in a space between the first surface of the case and the motor cover, a rotating shaft that is coupled to the driving motor and that is configured to transfer driving force generated by the driving motor to the traveling wheel, and a coupling unit that couples the rotating shaft to the traveling wheel, characterized in that the coupling unit includes: a rotating plate that includes a hub that is coupled to the rotating shaft, and a plurality of wheel-coupling bosses that protrude from the rotating plate toward the traveling wheel and that are symmetrically arranged about the hub. an air suctioning device that is configured to generate suction force, a case that includes an interior space accommodating the air suctioning device, a driving motor that is coupled to a first surface of the case and that is configured to generate driving force, a traveling wheel that is coupled to the first surface of the case and that is configured to rotate based on driving force generated by the driving motor, a motor cover that is configured to cover the driving motor such that the driving motor is located in a space between the first surface of the case and the motor cover, a rotating shaft that is coupled to the driving motor and that is configured to transfer driving force generated by the driving motor to the traveling wheel, and a coupling unit that couples the rotating shaft to the traveling wheel, characterized in that the coupling unit includes: a rotating plate that includes a hub that is coupled to the rotating shaft, and a plurality of wheel-coupling bosses that protrude from the rotating plate toward the traveling wheel and that are symmetrically arranged about the hub. a rotating plate that includes a hub that is coupled to the rotating shaft, and a plurality of wheel-coupling bosses that protrude from the rotating plate toward the traveling wheel and that are symmetrically arranged about the hub.