When a magnetically shielded room (MSR) to shield leakage fluxes of electric machines is designed by using magnetic field analysis, it is difficult to represent the leakage magnetic field of an electric machine accurately. In this paper, a method of modeling it using a simple solid model with multiple magnetization vectors is proposed. In this method, the magnetization vectors are determined by an inverse technique to represent a real leakage flux distribution. First, the proposed method is explained and verified using a simple 2-D linear magnetostatic one-phase transformer model. Then, the method is applied to a 3-D model and the effect of selected measured surface on representation of leakage flux is investigated. Finally, an experimental verification is carried out. It is shown that the proposed method can represent the leakage magnetic field with small number of magnetizations. The leakage flux only in the region behind the measured surface can be represented, and it is verified by experiment. Moreover, the shielding performance of MSR can be evaluated by using the proposed solid model with suitable permeability.