An electric supply apparatus configured to supply electric power in a contactless manner to an electric reception apparatus provided in a vehicle, using electromagnetic induction, the electric supply apparatus comprising: a transmitting section (122, 125) configured to transmit a first modulated signal of a first test data string having a predetermined data sequence, to the electric reception apparatus, using inter-coil communication; a control section that is configured to control the transmitting section to transmit the first modulated signal from the transmitting section; a receiving section configured to receive, from the electric reception apparatus, a second modulated signal of a second test data string obtained by demodulating the first modulated signal at the electric reception apparatus, using the inter-coil communication; and a determination section configured to determine whether there is an obstacle between the electric reception apparatus and the electric supply apparatus, based on whether the first test data string coincides with a demodulation result of the second modulated signal, characterized in that: the control section is configured to control the transmitting section to repeatedly transmit the first modulated signal from the transmitting section while increasing a transmission power level; and the determination section is configured to determine whether there is an obstacle between the electric reception apparatus and the electric supply apparatus, based on a transmission power level used for transmission of the first modulated signal from the transmitting section (122, 125), when the first test data string coincides with the demodulation result of the second modulated signal. a transmitting section (122, 125) configured to transmit a first modulated signal of a first test data string having a predetermined data sequence, to the electric reception apparatus, using inter-coil communication; a control section that is configured to control the transmitting section to transmit the first modulated signal from the transmitting section; a receiving section configured to receive, from the electric reception apparatus, a second modulated signal of a second test data string obtained by demodulating the first modulated signal at the electric reception apparatus, using the inter-coil communication; and a determination section configured to determine whether there is an obstacle between the electric reception apparatus and the electric supply apparatus, based on whether the first test data string coincides with a demodulation result of the second modulated signal, characterized in that: the control section is configured to control the transmitting section to repeatedly transmit the first modulated signal from the transmitting section while increasing a transmission power level; and the determination section is configured to determine whether there is an obstacle between the electric reception apparatus and the electric supply apparatus, based on a transmission power level used for transmission of the first modulated signal from the transmitting section (122, 125), when the first test data string coincides with the demodulation result of the second modulated signal. the control section is configured to control the transmitting section to repeatedly transmit the first modulated signal from the transmitting section while increasing a transmission power level; and the determination section is configured to determine whether there is an obstacle between the electric reception apparatus and the electric supply apparatus, based on a transmission power level used for transmission of the first modulated signal from the transmitting section (122, 125), when the first test data string coincides with the demodulation result of the second modulated signal.