High-speed milling (HSM) has advantages in high productivity high precision and low production cost. Thus it can be widely used in the manufacture industry. However, when the speed of spindle-tool reaches a higher speed range, the gyroscopic effect will become an important part of its stable milling. In this paper, a dynamics model of HSM system was proposed considering the influence of gyroscopic moment due to high rotating speed of end milling, and solution it. Then, the natural frequencies of end-milling model were researched by using analyse software. And analysis the stability of end-milling that considered gyroscopic effects under different speeds, obtain the Campbell Diagram. Get the trajectory of one point in end face milling. Then draw the fitting trajectory and ideal trajectory of the point in milling. Compare the actual trajectory, fitting trajectory and the ideal trajectory. So it can provide a basis for stability prediction of high speed milling.