High-speed multi-axis CNC milling machine is the high technology product. With the development and improvement of motor-drive-technology, the milling head braking method is especially important for high-speed multi-axis CNC milling machine. The advantages and disadvantages of the existing braking methods were analyzed. A new braking method for milling head was raised. The mechanical model of the braking system is established, and the influence parameters were given. The analysis of braking method can provide theoretical basis for improving braking effect, machining accuracy and quality of CNC milling machines.