A dynamic performance test method of a vehicle electric driving system belongs to the technical field of electric automobiles. A vehicular motor output shaft is connected and coaxial with a load motor output shaft, when in driving, power of a driving system is transmitted from a vehicular motor and a load motor to be transformed into electric energy to be stored in a super capacitor or consumed on a resistance box, when in braking, energy is transmitted from the super capacitor to be consumed by the resistance box and then fed back to a battery pack via the load motor and the vehicular motor, and then running of the load motor is controlled and actual load torque is simulated, further, a load simulation controller computes power consumed by driving resistance and power transformed to vehicle power according to current circulating speed, vehicle parameters and road conditions and controls resistance of the resistance box, namely controlling energy consumed by the resistance box to be equal to energy consumed by driving resistance. The dynamic performance test method of a vehicle electric driving system can be used for research on the driving control strategy individually and research on the braking control strategy, and simultaneously can be applied to research on the total vehicle control strategy more conveniently.