A low-speed large-torque high water-based hydraulic motor with self-balanced distributing valves is proposed so as to meet the needs in condition of high water-based medium and low to middle larege torque. Firstly, the work principle of structure of the high water-based hydraulic motor with self-balanced distribution valve was illustrated. Then, the overall model of the motor was built by AMESim to simulate with analysis of the dynamic characteristics. The influences of factors such as different opening displacements of valve and load torque on the performance of motor were simulated with research separately. The analysis provides reference for the design and manufacture of the low-speed large-torque high water-based hydraulic motor.