Abstract: The lower limb prosthesis has severe nonlinearities and coupling such that an accurate dynamic model is difficult to build, making it very challenging to control the prosthesis. Hence, a subsection control strategy is proposed to resolve these difficulties. First, the VICON MX 3D gait analysis system is used to collect the lower limb movement information, and then the gait of the sound section is divided into stance and swing phases based on plantar pressure. Next, the dynamic model of the two stages is established based on the Lagrange equation. Furthermore, a subsection control strategy is developed. Then, based on TDE, sliding mode control is studied in the swing phase and combined with the target impedance control used in the stance phase. Finally, compared with the model-based sliding control method, the motion trajectories of each joint are tracked. The simulation results showed that the proposed method can compensate for the strong nonlinearity and various uncertain factors in the lower limb prosthesis system, simplify the calculation of the model, and improve the control effect of the prosthesis.