The utility model relates to an automatic fire damper cleaning device which comprises a fire damper body, a telescopic hose, a self-locking mechanism, a displacement executing mechanism and a cleaning mechanism. The telescopic hose is arranged between the fireproof valve body and the air pipe, the self-locking mechanism is arranged between the telescopic hose and the fireproof valve body, the displacement executing mechanism is arranged above the fireproof valve body, and the cleaning mechanism is arranged on one side of the air pipe and comprises a plurality of air compression nozzles arranged in the height direction and an air source device connected with the air compression nozzles. By the adoption of the technical scheme, dust, hemp threads and other obstructions on the blades of the valve body of the fireproof valve can be rapidly and efficiently cleaned away.