Disclosed is a wireless charging system of using multi-frequency including at least one transmitter and at least one receiver which is wirelessly charged by the at least one transmitter, wherein the at least one transmitter includes a signal generator configured to generate a power signal of each of a plurality of frequency bands; a plurality of matching units connected to the signal generator matching and outputting the power signal of each of the plurality of frequency bands; and at least one antenna connected to the plurality of matching units transmitting the power signal of each of the plurality of frequency bands to each of at least one receiver, and wherein the at least one receiver includes at least one antenna receiving a power signal of each of a plurality of frequency bands from each of at least one transmitter; a plurality of matching units connected to the at least one antenna matching and outputting the power signal of each of the plurality of frequency bands; and a plurality of rectifiers connected to the plurality of matching units rectifying AC power applied to the power signal of each of the plurality of frequency bands to DC power.