The invention discloses a high-flexibility and low-energy bionic tension and compression ankle joint for a biped robot. In the high-flexibility and low-energy bionic tension and compression ankle joint, the interaction between a passive flexible member and an antagonistically-arranged active drive flexible member achieves the back extension and plantar flexion the bionic tension and compression ankle joint for the biped robot. A curved sole plate design makes the movement gait of the biped robot closer to human walking. The passive flexible member itself has preloading force and flexibility and enhances the smoothness and flexibility of the ankle joint movement during transmission movement. In addition, a three-dimensional topological structure formed by the active drive flexible member and the passive flexible member can not only maintain the stability of the ankle joint but also contribute to the transmission and management of energy. Thus, the passive flexible member, the active flexible member and a hard member constitute a bionic tension and compression structure, which contributes to improving the flexibility and energy efficiency of the biped robot.