Abstract: The mathematical model of a single-magnet magnetic suspension system is presented on the basis of analyzing the structural characteristics of a magnetic suspension system of the electric magnetic system(EMS) MAGLEV.Stochastic linear quadratic optimal control strategy is used to design the controller.The control effect of this magnetic suspension control system to the time history of the magnet gap for a gap initial condition and a force disturbance under different performance index weight matrices is(researched).Finally,the simulation results are given to provide a reference for the design of the magnetic suspension control system.