A wireless power transmission unit comprising: first and second wireless power transmitting sections (10a, 10b), each of the first and second wireless power transmitting sections including an oscillator configured to convert DC energy into RF energy having a frequency f0, a power transmitting antenna configured to transmit the RF energy and includes a first inductor and a first capacitor connected together in series to form a series resonant circuit with a resonant frequency fT, and a power receiving antenna configured to receive at least a part of the RF energy transmitted by the power transmitting antenna by coupling a resonant magnetic field and includes a second inductor and a second capacitor connected in parallel with each other to form a parallel resonant circuit with a resonant frequency fR, wherein the resonant frequencies fT and fR are set to be substantially equal to the frequency f0 of the RF energy, and wherein if Voc represents the voltage step-up ratio of the oscillator, L1 and L2 represent the inductances of the power transmitting and power receiving inductors (107a, 109a), respectively, and k represents the coupling coefficient of the power transmitting and power receiving antennas, these L1, L2, k and Voc values are determined so as to satisfy the following inequality: L ⁢ 2 / L ⁢ 1 ≧ 4 ⁢ k / Voc 2 a combining section configured to combine together RF energies supplied from the respective power receiving antennas of the first and second wireless power transmitting sections and to output the combined RF energy; and a control section configured to control the respective oscillators of the first and second wireless power transmitting sections such that the respective phases of the resonant magnetic fields of the first and second wireless power transmitting sections have a phase difference θres of 90 to 180 degrees therebetween. first and second wireless power transmitting sections (10a, 10b), each of the first and second wireless power transmitting sections including an oscillator configured to convert DC energy into RF energy having a frequency f0, a power transmitting antenna configured to transmit the RF energy and includes a first inductor and a first capacitor connected together in series to form a series resonant circuit with a resonant frequency fT, and a power receiving antenna configured to receive at least a part of the RF energy transmitted by the power transmitting antenna by coupling a resonant magnetic field and includes a second inductor and a second capacitor connected in parallel with each other to form a parallel resonant circuit with a resonant frequency fR, wherein the resonant frequencies fT and fR are set to be substantially equal to the frequency f0 of the RF energy, and wherein if Voc represents the voltage step-up ratio of the oscillator, L1 and L2 represent the inductances of the power transmitting and power receiving inductors (107a, 109a), respectively, and k represents the coupling coefficient of the power transmitting and power receiving antennas, these L1, L2, k and Voc values are determined so as to satisfy the following inequality: L ⁢ 2 / L ⁢ 1 ≧ 4 ⁢ k / Voc 2 a combining section configured to combine together RF energies supplied from the respective power receiving antennas of the first and second wireless power transmitting sections and to output the combined RF energy; and a control section configured to control the respective oscillators of the first and second wireless power transmitting sections such that the respective phases of the resonant magnetic fields of the first and second wireless power transmitting sections have a phase difference θres of 90 to 180 degrees therebetween.