In this paper, a new design method using space mapping algorithm is presented for the design of magnetic systems. The method mathematically combines the magnetic equivalent circuit method and the finite element method and the optimal design is achieved by employing a quasi-Newton iteration in conjunction with first-order derivative approximations updated by the classic Broyden formula. Therefore, this method can preserve the computational efficiency of the magnetic equivalent circuit method and the accuracy of finite element method. Two numerical examples are tested to prove feasibility and numerical efficiency of the implementation of the proposed design method.Index Terms-Finite element method, magnetic circuit method, parameter extraction, space mapping.