Based on the technologies of three dimensional (3D) modeling and dynamic simulation analysis, the Virtual prototype of fiveaxis computer numerical control (CNC)tool grinder was built.The size of grinding force and changing trend during the fiveaxis CNC tool grinder working was simulated. Then the validity of the dynamic model was confirmed by the oretical calculation.Whats more, the influence factors such as wheel speed, grinding depth and feeds on grinding force were researched, which can provide are ference to the design offiveaxis CNC tool grinder.