The utility model relates to a hydraulic bale cutter. The hydraulic bale cutter is characterized in that a hydraulic drive system and a hydraulic control system are arranged on a rack of the hydraulic bale cutter, wherein the hydraulic drive system and the hydraulic control system are used for driving bale cutting knives to cut bale blocks on a bale cutting disc. Between two bale cutting operations, the hydraulic control system and the hydraulic drive system drive the bale cutting knives and the bale cutting disc to rotate by relative 90 degrees in the axial direction. The hydraulic bale cutter has the advantages that structure is simple, and design is reasonable; the bale blocks can be cut into pieces in one cutting period, the phenomenon of bonding can be reduced, the use amount of parting agents is reduced, and on-line continuous type cutting production can be achieved; small bale blocks after cut do not need to be baked to become soft and can be directly put into subsequent production, procedures are simplified, and quality of rubber compound is improved; the cross section of a knife rest and the cross section of an inner cavity of the rack are round, large abrasion after cutting edges are used repeatedly can not happen, and the service life of the bale cutting knives is prolonged; a nylon layer is arranged on the surface, bearing the cut bale blocks, of the bale cutting disc, and therefore surface abrasion or damage on the bale cutting disc after repeated cutting can not happen.