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. Finite element model (FEM) is used to model the dynamics of a spindle-milling system. It obtains the trajectory of central point in face milling with considering gyroscopic effects through the dynamics model at high speeds. Then the cutting force model will be corrected by the trajectory of face milling. So it can provide a basis for stability prediction of high speed milling.