Due to the ease and excellence of the hydraulic transmission, this research is concerned to transmit power from tractor to a reciprocating mower using a hydraulic cycle. The theoretical consideration and the previous results from different studies were used to determine a suitable of a hydraulic motor, which give a sufficient torque needed to cutting different stems. Field experiments were performed on clover crop "M.C" of 25.92%, w.b., to evaluate the performance of the developed mower. At forward speeds of 0.89, 1.29, 1.42 and 1.72 m/s and knife speeds of 2.2, 2.6 and 2.9 m/s. Results showed that, after development operation, the consumed power and actual cutting height decreased by 17.32% and 10% respectively at forward speed of 1.72 m/s with cutting knife speed of 2.2 m/s. Furthermore, the actual field capacity increased by 9% under the same previous variables. To achieve the highest efficiency of cutting height, which is 90.2%, it is recommended to operate the cutting knife at a speed of 2.9 m/s with a forward speed of 0.89 m/s for developed mower.