To meet the need of guidance law visualization in research and teaching, take the three-dimensional pure pursuit guidance law as an example, the three-imensional simulation model was established based on Matlab/Simulink. The virtual-reality modeling language(VRML) was used for establishing the three-dimensional visual scene and joystick was used for controlling target motion, an interactive three-dimensional pure pursuit guidance law's Simulink model was built. The missile's trajectory also changed with motion of the target. The whole flight process from different angle was demonstrated, and the guidance law can be completed much better.