Aiming at the design of the adjustment scheme for the hexapod external fixator and the optimization of the position and posture changing trajectory of the fixator during the deformity correction of the foot and ankle, a method of adjustment scheme for the external fixator based on the neural network is proposed. Firstly, the kinematics of the hexapod external fixator is analyzed with the neural network. Secondly, different deformity correction modes including ankle mode, miter mode, butt mode and parallel mode, are discussed. Finally, a computer-aided adjustment scheme of the hexapod external fixator is proposed and the adjustment sequence of telescopic screws is discussed in the calculation. Experimental results show that the adjustment scheme which designed based on the proposed method could effectively guide the correction of different types of foot and ankle deformities. They could achieve ideal remained deformity and the average residual displacement deformity is less than 1 mm and the average residual angular deformity is less than 1°. Meanwhile, with this adjustment scheme, the position and posture changing trajectory of the hexapod external fixator could be closer to the ideal linear trajectory, and the offset of optimized position changing trajectory and optimized posture trajectory changing are reduced by 31% and 19% respectively, which effectively alleviate the pain of patients and improved the experience of deformity correction.