FIG. 3 is a diagram illustrating an equivalent circuit of the wireless power transmission system 1 illustrated in FIG. 2. In FIG. 3, an alternating-current power generating unit 211 generates and outputs alternating-current power with a frequency corresponding to the resonance frequency. A power supply unit load 212 exhibits a value equal to characteristic impedances of the connection lines 115, 116 and the connection lines 125, 126, and has a value of Z0. An inductor 213 corresponds to the inductors 113, 114 and has an element value of L1. A resistor 214 exhibits resistance which accompanies a transmission side circuit, mainly the inductor, and has an element value of R1. A capacitor 215 is a capacitor of an element value C1 occurring between the electrodes 111, 112. A capacitor 221 is a capacitor of an element value C2 occurring between the electrodes 121, 122. An inductor 222 corresponds to the inductors 123, 124 and has an element value of L2. A resistor 223 exhibits resistance which accompanies a reception side circuit, mainly the inductor, and has an element value of R2. A load 224 is supplied with power outputted from the alternating-current power generating unit 211 and transmitted via the power transmission coupler and the power reception coupler. A capacitor 241 denotes a capacitor occurring between the electrodes 111, 112 and the electrodes 121, 122 and has an element value of Cm1. Note that the load 224 is, for example, constituted of a rectifying device, a secondary battery, and so on. Of course, it may be constituted of other elements.