A wireless energy transfer device (1) includes: a power transmission unit (2) that generates an oscillating magnetic field or oscillating electric field; a power reception unit (3), which is provided with a receiving antenna (31), and which converts the oscillating magnetic field or the oscillating electric field of the power transmission unit (2) to electric power by the receiving antenna (31); and an electric power theft suppression unit that suppresses the theft of energy with the oscillating magnetic field or the oscillating electric field of the power transmission unit (2).