As an important and complex mechanical and electrical part of CNC machine tools,the position servo system is difficult to control and affected by many factors,however,its position precison will affect the machining accuracy of CNC machine tools.In this paper,we use the Compact Format Dynamic Linearization (CFDL) and traditional PI control to improve the speed loop and position loop,and then improve the design of Model-Free Adaptive Control (MFAC) by adding control items.The Matlab/Simulink simulation results show that the proposed scheme keeps the advantages of MFAC,and improves in position following performance as well as robustness.