In the paper, a high speed magneto-optic switch based on the Faraday Effect is designed and analyzed. The optic switch adopts Faraday rotator, nanosecond impulser, and high speed magnetic field, so it is characterized by no moving parts, low transmission loss and polarization insensitive, low optical insertion loss etc. Using the polarization and Faraday Effect of magneto-optic crystal, the magneto-optic switch can hold the function of all-optical switching, which is needed in all-optical communication networks. As the first part of this paper, a design scheme of optical route in high speed magneto-optic switch and its experiment analysis will be discussed. Good avalanche effect of transistor 2N5551 is adopted to generate nanosecond pulse signal and then to drive the high speed magnetic field. Shown by the experiment data, the rising time of the impulse about 10ns, the amplitude of the impulse about 10~60V are available on the Output end from the nanosecond impulser, which can be used as driving current pulse of Faraday rotator. By using the relationship between the polarization plane rotate direction of polarization light and magnetic direction, the Faraday rotator is designed. It's unique double magnetic field and externally applied static magnetic design can greatly speed the excitation time of the internal inductive magnetic field and shorten the switching time of magneto-optic switch.