A power transmitter and a power receiver are arranged with a space therebetween. A power transmitting device generates a resonant current by taking out electric energy from a DC power supply through an operation of a power transmitting switch circuit, directly creating, in a space, by using the resonant current, an electromagnetic field that periodically changes at a switching frequency, and forms an electromagnetic resonance field in which the space itself has energy and vibrates. A power receiving device generates a resonant current by obtaining electric energy from the resonance field and forms a new electromagnetic field on the basis of this resonant current. The power transmitting device or the power receiving device, when viewed as a geometric figure, is a fractal-shaped device formed of a line conductor pattern in which a portion is similar to the whole, and increases electromagnetic field energy in a space surrounding the fractal-shaped device.