The invention discloses a drill rod automatic cleaning device. The drill rod automatic cleaning device comprises at least two pairs of lifting idler wheels and a cleaning mechanism, wherein the two pairs of lifting idler wheels are arranged on a conveying line of a drill rod separately, a clamping part for supporting the drill rod is arranged between each pair of lifting idler wheels, the cleaning mechanism comprises a gate-shaped framework, a high-pressure cleaning pump and a plurality of spraying nozzles communicated with the high-pressure cleaning pump, the multiple spraying nozzles are fixedly arranged on the gate-shaped framework, the gate-shaped framework is vertically arranged above the conveying line of the drill rod, and the drill rod passes through the gate-shaped framework when conveyed. The drill rod automatic cleaning device efficiently cleans the inside and the outside of the drill rod, relieves the labor intensity for workers, and improves work efficiency.