A wireless power transmission apparatus for a wireless power transfer system in which the wireless power transmission apparatus transmits high-frequency power to a plurality of wireless power reception apparatuses (3-1, 3-2, 3-N), wherein the wireless power transmission apparatus comprises: a power transmission antenna (22-1, 22-2, 22-N) adapted to transmit, to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), each of a plurality of high-frequency power corresponding to a first frequency and each of a plurality of high-frequency power corresponding to a second frequency; characterized by a plurality of receiver circuits (23-1, 23-2, 23-N) adapted to obtain, from each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N): i) a required voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), ii) a first power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and that corresponds to the first frequency, and iii) a second power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and that corresponds to the second frequency; and a control circuit adapted to sum first errors to obtain a first sum total, wherein each of the first errors occur between i) the required voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N) and ii) the first power reception voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N), wherein the control circuit is further adapted to sum second errors to obtain a second sum total, wherein each of the second errors occur between i) the required voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N) and ii) the second power reception voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N), wherein the control circuit is further adapted to transmit, to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), each of a plurality of high-frequency power corresponding to a third frequency, which is close to a frequency corresponding to a smaller sum total of the first sum total and the second sum total, to converge each of third errors occurring between i) the required voltage value and ii) a third power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and to the third frequency, to be within a predetermined criterion error. a power transmission antenna (22-1, 22-2, 22-N) adapted to transmit, to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), each of a plurality of high-frequency power corresponding to a first frequency and each of a plurality of high-frequency power corresponding to a second frequency; characterized by a plurality of receiver circuits (23-1, 23-2, 23-N) adapted to obtain, from each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N): i) a required voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), ii) a first power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and that corresponds to the first frequency, and iii) a second power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and that corresponds to the second frequency; and i) a required voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), ii) a first power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and that corresponds to the first frequency, and iii) a second power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and that corresponds to the second frequency; and a control circuit adapted to sum first errors to obtain a first sum total, wherein each of the first errors occur between i) the required voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N) and ii) the first power reception voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N), wherein the control circuit is further adapted to sum second errors to obtain a second sum total, wherein each of the second errors occur between i) the required voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N) and ii) the second power reception voltage value that corresponds to each of the plurality of the receiver circuits (23-1, 23-2, 23-N), wherein the control circuit is further adapted to transmit, to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N), each of a plurality of high-frequency power corresponding to a third frequency, which is close to a frequency corresponding to a smaller sum total of the first sum total and the second sum total, to converge each of third errors occurring between i) the required voltage value and ii) a third power reception voltage value that corresponds to each of the plurality of the wireless power reception apparatuses (3-1, 3-2, 3-N) and to the third frequency, to be within a predetermined criterion error.