In order to ensure that the drive motor used in the CNC bending machine can work normally without performance waste, a comprehensive, accurate and practical motor selection method was proposed according to the kinematic and dynamic characteristics of the drive shaft. The multi-body dynamics simulation software ADAMS was used to establish the multi-body dynamics model for a CNC bending machine. According to the seven segment S-shaped acceleration and deceleration curve, the motion planning of the die tip of the CNC bending machine was carried out by using MATLAB, and combined with the motion planning and the multi-body dynamic model established by ADAMS, the speed and load torque of the driving shaft were obtained. The motor was selected from four aspects including the peak speed, torque, thermal balance, inertia matching and torque speed characteristic curve, and verified by experiment. The results show that the proposed method can not only ensure the working efficiency of the bending machine, but also give full play to the performance of the motor.