This paper studies the model for the three-phase contactless power transfer system. A phase winding in the three-phase contactless power transformer has the magnetic couplings with all of the other phase windings. Moreover, the magnetic couplings depend on the displacement of the secondary armature with respect to the primary armature. The equivalent model of the three-phase system with the complicated mutual inductances due to such magnetic couplings is presented. The model is transformed into the single-phase model that is similar to the model for the conventional system. The simplified model allows the easy consideration of the operation of the three-phase system. By using the model, the resonant capacitances for the three-phase system are available. The model is confirmed to successfully simulate the performance of the actual system. In addition, the experimental and theoretical results confirm that the three-phase system has the stable performance of the power transfer independently of the displacement of the secondary.