The invention discloses a novel cleaning device for the inner wall of a hydraulic cylinder barrel, and the novel cleaning device is used for cleaning the inner wall of the cylinder barrel. The novel cleaning device comprises a machine base which extends in the horizontal direction, a fixed frame which is fixedly mounted at the left upper end of the machine base, a cleaning assembly and a transverse regulating assembly, wherein a longitudinal slide slot which is provided with a rightward opening and extends up and down is formed in the fixed frame; a slide frame can be mounted in the longitudinal slide slot in an up-down sliding mode; a transverse slide slot which is provided with an upward opening and extends left and right is formed in the upper end of the machine base; a threaded rod canbe rotatably mounted between left and right end walls of the transverse slide slot; the left end of the threaded rod is in power connection with a slide motor fixedly mounted on the machine base; thetransverse regulating assembly comprises a slide supporting base which is mounted in the transverse slide slot in a sliding mode and is in threaded fit to the threaded rod; an arc-shaped slot which extends left and right is formed in the slide supporting base; and a fastening clamp for fastening the cylinder barrel is further arranged in the supporting base.