A wireless power transfer system includes a first transmitter coil, a second transmitter coil and a third transmitter coil arranged such that normal directions to planes of the first, the second and the third transmitter coils are orthogonal to each other in a three-dimensional space, and a controller that controls electric currents supplied to the first, the second and the third transmitter coils such that a synthetic magnetic field vector produced by the first, the second and the third transmitter coils rotates in a plane of rotation at a first angular frequency “ω”, and that a normal vector to the plane of rotation rotates about an axis of rotation perpendicular to the normal vector at a second angular frequency “a” equal to or smaller than the first angular frequency (a≤ω).