Magneto-Optical modulation technology has become key component in many optical information systems. However, due to the abstract theoretical knowledge, many textbooks do not introduce the properties of circular anisotropy, so it is difficult for most students to understand the polarization properties of light accurately and in depth. In this paper, the processes of Magneto-Optical modulation are Three-Dimensionally dynamically simulated by using MATLAB software first. These simulations make the complex and abstract light propagation processes become visual, which are effective aids for optics’ teaching. These simulations can enhance the understanding of the concept and the interactions with media of polarized lights and the principles of Magneto-Optical modulation. Second, a magnetic rotation glass is used to produce Magneto-Optical modulator, and finally the optical communication simulation experiment is realized and the effect is good. Experimental results show that the magneto-optical modulator has advantages like low power requirements, low modulation voltage, simple device, flexible, long life-time and small affect to the external temperature etc.