A robot cleaner includes a main body that autonomously travels, a suction nozzle configured to move up and down or swing with respect to the main body, and a support to support the suction nozzle. The robot cleaner may respond to a change in a height of a floor to improve travel performance and may respond better to obstacles. Even when a height difference of the floor is large, cleaning performance may be improved by maintaining contact and increasing a suction pressure of the suction nozzle.