Aimed at existing problems on the bending performance of pneumatic bending joint, a new type of pneumatic bending joint is proposed in this paper. Double flexible pneumatic actuators are used as actuating drivers. Based on the first law of thermodynamics and the joint dynamic equation, the angle dynamic model is established and analyzed. Moreover simplified model is proposed. Meanwhile, its dynamic characteristic is analyzed through simulation analysis. The simulation suggests the following results: in the gas-filled phase, the joint’s pressure response time is about 10ms; while it is about 60ms in the gas-escape phase; and the angle response time of joint is 10 to 20ms. When the joint damping coefficient is increasing, this value will also increase.