Disclosed is a robot cleaner system having superior functions of sucking dust and exhausting dust to a docking station. The robot cleaner includes a dust suction port to suck dust, a dust collecting chamber to collect dust introduced through the dust suction port, a dust exhaust port to exhaust dust collected in the dust collecting chamber to the docking station, a connection path extending from the dust suction port to the dust exhaust port in adjacent to the dust collecting chamber, and a valve device provided between the connection path and the dust collecting chamber, an opening/closing of the valve device allowing the dust collecting chamber to selectively communicate with the dust suction port or the dust exhaust port according to a pressure difference between the dust collecting chamber and the connection path.