In order to improve the safety and comfort of humanmachine interaction and its adaptability to complex unstructured environments, a new type of ankle joint based on a series of elastic drive and rigid drive hybrid is designed between the motor and exoskeleton robot. Linear spring groups were introduced to achieve flexible driving and to absorb the ground reaction force and other impact vibration. At the same time, a disk brake device was designed to retain the rigid drive function to quickly and accurately respond to the motion of the human ankle joint and to reduce humanmachine movement deviation. The dynamic model of the ankle joint was established. The stability of the hybrid driver under different parameters and the force following characteristics were obtained through frequency domain analysis. Through simulation experiments, the cushioning and damping characteristics of the exoskeleton ankle joint are verified, and the accuracy and effectiveness of the model are verified as well.