A power feeding coil unit (a coil unit) is provided with a power feeding coil (a coil for power transmission) and an apparatus for detecting foreign matter. The apparatus for detecting foreign matter is provided with a plurality of resonators having a resonator coil and capacitor and also an excitation coil for exciting the plurality of resonators. The plurality of resonators are disposed in rows and columns to cover at least an area interlinking with a magnetic flux generated by the power feeding coil. The excitation coil makes resonators adjacent in a row direction and a column direction among the plurality of resonators to generate an alternating magnetic field with resonance frequencies different from each other within a frequency band in which the power feeding coil is not excited.
