The utility model discloses a hydraulic motor which comprises a shell, wherein a connecting rod-plunger piston component is arranged in the shell; a plunger piston sleeve is arranged on the peripheral surface of the shell. The hydraulic motor is characterized in that the plunger piston sleeve comprises a cylinder cover and a cylinder sleeve hermetically matched with the cylinder cover; the cylinder cover is arranged at the end part of the peripheral surface of the shell; the cylinder sleeve is arranged in the shell and wraps the connecting rod-plunger piston component. Compared with an existing integrated plunger piston sleeve, the hydraulic motor has the advantages that the plunger piston sleeve is divided into the two parts, namely the cylinder cover and the cylinder sleeve; the cylinder sleeve is made of materials with better stress performance; the cylinder cover is made of general materials, so that the manufacturing cost of the plunger piston sleeve is powerfully reduced; meanwhile, in the split plunger piston sleeve, the cylinder sleeve does not easily transfers acting force to the cylinder cover under the action of alternating stress of the plunger piston, so that the transfer of the alternating stress is cut off, and the stability of working conditions of the hydraulic motor is improved; the cylinder sleeve is better and simpler in shape and is convenient to process, and the improvement of the processing precision is facilitated, so that the wear-resisting property between the cylinder sleeve and the plunger piston used as a pair of friction pairs can be improved.