An modeling method of magnetic device with transformer and inductor is proposed, which combining with advantages of magnetic circuit- electric circuit dual transformation method and and gyrator- capacitance transformation method.The model of magnetic circuit- electric circuit dual transformation method is simple and can better reflect the circuit characteristics, and gyrator-capacitance transformation modeling can reflect the characteristics of magnetic circuit simultaneously. Therefore, the new modeling method proposed in this paper can reflect the characteristics of magnetic circuit and electric circuit at the same time, as well as physical concept of the parameters. According to electromagnetic theory, unified model which reflecting magnetic circuit and the circuit is established, and the nonlinear inductance simulation model of reflecting hysteresis effect is proposed based on the strict mathematical derivation and reasonable simplification. Hysteresis loop simulation results consistent with the hysteresis loop in magnetic core manual, confirmed the correctness and effectiveness of the proposed magnetic device modeling method. Modeling and analysis the coupling inductance using the proposed modeling method, the result indicates that is practical.