This power transmission apparatus transmits power to a power reception apparatus by means of a magnetic field resonance system by supplying an output AC voltage (VE) of a class E amplifier to a power-transmission side resonance circuit (TT). Before the transmission of power, the output AC voltage (VE) of the class E amplifier is divided, and a voltage obtained by the division is supplied to the power-transmission side resonance circuit (TT). A current amplitude detection value of a power-transmission side coil (TL) at this time is obtained as an evaluation value, and whether to permit execution of power transmission is controlled on the basis of the evaluation value, through determination as to whether a foreign object is present or not.