The invention relates to a pruning machine which comprises a reversal resetting device, a blade and a blade bracket, wherein grooves are respectively arranged on the blade; eccentric cams are respectively arranged in the grooves; the blade is adapted with the reversal resetting device by the blade bracket; the reversal resetting device comprises an output shaft, a bull wheel which is coaxially adapted with the output shaft, and a torsion spring; and the bull wheel is connected with the output shaft by the torsion spring. The invention automatically releases energy due to elastic deformation when the blade is clamped by utilizing energy stored when the torsion spring works by the skillful matching of the torsion spring with the bull wheel and the output shaft and drives the output shaft toreverse so as to drive the blade to automatically reset and reverse, protects cutter teeth on the blade without clamping hard objects, such as steel wires, and the like, is difficult to damage the blade and improves the safety of a consumer in use.