A non-contact power feeding coil of the present invention is a power feeding coil (3) that configures a non-contact power feeding system (1), the power feeding coil being provided with a coil (35) through which an AC current of a specific frequency flows, and a core (31) that forms a section of a circulating magnetic path, which is interlinked with the coil, in which in the coil, a wire (36) having an insulating covering (38) is wound around a conductor (37), and a covering thickness (Ti) of the insulating covering is set so that the influence of a proximity effect that occurs at the specific frequency between adjacent portions of the wire is a predetermined amount or less. According to this configuration, it is possible to freely adjust a separation distance between portions of the conductor by altering the covering thickness; and therefore, the occurrence of AC loss caused by a proximity effect is appropriately suppressed.