A kind of new type three-phase magnetism valve type controllable reactor is proposed in this article, its structure and the principle are introduced. The article carried the electromagnetism analysis on the new type magnetism valve type controllable reactor, and established the three-phase magnetism valve type controllable reactor two-dimensional simulation model with Ansoft electric-magnetic field analysis software. Simulation results verified the feasibility of adjusting the reactor reactance smoothly by adjusting the thyristor's triggering angle. Lastly, it made an analysis about three-phase magnetism valve type controllable reactor's electromagnetism field distribution.