A power transfer system (301) includes a power transmission device (101) and a power reception device (201) which are capacitively coupled to allow electrical conduction therethrough in the manner of alternating current. The power transmission device (101) includes an active electrode (3), a passive electrode (2), a step-up transformer (11), and a high-frequency voltage generating circuit (10). The power reception device (201) includes an active electrode (6), a passive electrode (7), and a load circuit (5). A divider for voltage division based on load capacitances (C1 and C2) is provided between the active electrode (3) and the passive electrode (2). The active electrode (3) and the passive electrode (2) have respective equivalent capacitances to ground (Ca and Cp) relative to the ground potential. A ground leakage current Ig is minimized by adjusting the values of the respective capacitances in an equivalent circuit so as to satisfy the relationship: C2/C1 = Cp/Ca.