Abstract: To solve the rating current falling problem of the linear motor induced by the demagnetization of permanent magnet at high temperature and the decrease of coil's cooling capacity, the material selection and structure optimization design are emphasized in the research area of linear motor. In this paper, the permanent magnet material, winding parameters, air gap structure and so on sides were focused on for the linear motor optimization design of 6 channels direct drive servovalve(DDV). Firstly, a finite element simulation model of the linear motor was established with Ansoft Maxwell software. And then, the parameters of winding structure were optimized, including the width and height of air gap structure, ampere turns of coil, considering the permanent magnet material. Finally, some simulation and experiment tests were carried out. The results show that, the high temperature resistance and output force of the optimized linear force motor can be significantly improved. The maximum working temperature can reach 200 degrees Celsius, and the driving force can over 100 N.