This paper deals with a passivity-based approach to wide area stabilization of magnetic suspension systems. It is well known that the magnetic suspension systems have strong nonlinearity. In order to realize wide area stabilization of magnetic suspension systems, we design the passivity-based feedback controller considering a nonlinear dynamics of the magnetic suspension systems and a leakage inductance of the electromagnet especially. The systems can be decomposed two subsystems; an electrical subsystem and a mechanical subsystem. We design nonlinear passivity-based controllers for both two subsystems. Steady-state and transient time responses results for some operating points show the effectiveness of the proposed controller experimentally.