The invention relates to a cleaning and painting device for a street lamp post. The cleaning and painting device comprises a first rolling shaft, a second rolling shaft, a support, a hinge and a motor. A first left supporting rod is embedded in the middle of the first rolling shaft, and movable sleeves are arranged at the two ends of the first left supporting rod. The support is arranged at the lower ends of a first connecting rod and a second connecting rod, and a cleaning pipe is arranged on the left side of the support. An annular pipe is arranged inside a paint spraying pipe and connectedwith atomization heads. The motor is arranged on the left side of the first rolling shaft, and the right end of the motor is connected with a first gear. The lower portion of the first gear is connected with a second gear. The cleaning and painting device for the street lamp post can adapt to street lamp posts with the different diameters and is wider in application range; the rotating angle rangeof an upper half pipe body is 0-180 degrees so that the cleaning pipe can be fixed to the surface of the street lamp post conveniently, and a sponge block inside the cleaning pipe cleans the surfaceof the street lamp post; and the atomization heads are arranged on the inner side of the paint spraying pipe at the same angle so that paint can be sprayed on the surface of the street lamp post uniformly.