In order to solve the problem that the existing hydraulic motor is easy to be damaged due to unbalanced radial force, a couple force-type radial piston motor was designed based on the idea of double stators. The radial force balance of motor output shaft was not affected by the lateral force, and the torque was output through the force couple. The inner and outer motors were formed in one shell of the motor, and three kinds of torque and rotational speed can be output through different flow distribution modes. The structural characteristics and working principle of the motor were introduced, and the relationship between curve of guide rail and pulsation of motor torque and rotational speed were analyzed through the analysis of instantaneous torque of motor, the condition that torque and rotational speed of the motor without pulsating was obtained, and the law of angle distribution of guide rail curve when the torque ripple was zero was obtained. A motor test bench was built to test and measure the output characteristics of the motor. When the inner motor worked alone, the output torque was low and the rotation speed was high;when the outer motor worked alone, the torque was high and the rotation speed was low;when the inner and outer motors worked together, the maximum torque and minimum rotation speed were output. The motor prototype was processed and tested, and the output characteristics of the motor under three working modes were tested. The results showed that the torque pulsation was related to the sum of velocities of plungers in the oil inlet section. If the sum of the velocities was constant, there was no torque-speed pulsation in theory.