A type approval test platform for hydraulic motor was designed,which mainly involved hardware system,measurement and control system and test software.The maximum test pressure of the platform was 40 MPa,the maximum test flow rate was 1 000 L/min,the maximum test rotation speed was 3 000 r/min and the maximum test torque was 45 000 N·m.The test accuracy level of the system was class A,which could basically meet the type test requirements for hydraulic motors with different specifications and models.The platform was used to test the volumetric efficiency,total efficiency,the lowest speed and starting efficiency of low speed high torque hydraulic motor and cycloid hydraulic motor with 10 different specifications.The results show that the total efficiency and the lowest speed of several hydraulic motors are not in compliance with the requirements of industry standards,the quality of these products needs to be improved.The platform has been used for the third-party inspection of hydraulic motor products.