To provide a dust suction device for an air-conditioner, having improved reliability by preventing the deposition and accumulation of dust sucked by a fan of the dust suction device on the surface of the fan to prevent the degradation of dust sucking performance due to a reduction of the suction air volume of the dust suction device.

The fan 34 of the dust suction device 30 is periodically reversely rotated for separating and removing the dust deposited on the surface of the fan with the effects of centrifugal force during the reverse rotation of the fan, thus preventing a reduction in the suction air volume of the dust suction device with the deposition and accumulation of the duct sucked by the fan 34 of the dust suction device 30 on the surface of the fan.