A wireless power receiver (20, 700) that is configured to receive power from a wireless power transmitter (10, 600), the wireless power receiver (20, 700) comprising: a wireless communication unit configured to communicate with the wireless power transmitter(10, 600); and a controller, wherein the wireless communication unit is configured to transmit a first foreign object detection status packet and a second foreign object detection status packet to the wireless power transmitter (10, 600), wherein the wireless communication unit is configured to receive a foreign object detection indicator indicating that the foreign object is present in the charging area when the foreign object is present in the charging area based on the first foreign object detection status packet or the foreign object is present in the charging area based on the second foreign object detection status packet and wherein the controller is configured to proceed to a first power transmission procedure when the foreign object is not present in the charging area based on the first foreign object detection status packet and the foreign object is not present in the charging area based on the second foreign object detection status packet, or is configured to proceed to a second power transmission procedure that requests termination of power transmission or proceed to a third power transmission procedure different from the termination of the power transmission when the foreign object is present in the charging area based on the first foreign object detection status packet or the foreign object is present in the charging area based on the second foreign object detection status packet, characterized in that: the first foreign object detection status packet includes a reference quality factor, and the second foreign object detection status packet includes a reference peak frequency, wherein the foreign object detection indicator is determined using a measurement quality factor value of a power signal transmitted from the wireless power transmitter (10, 600) and the reference quality factor of the first foreign object status packet, or determined using a measurement peak frequency of the power signal transmitted from the wireless power transmitter (10, 600) and the reference peak frequency of the second foreign object status packet. a wireless communication unit configured to communicate with the wireless power transmitter(10, 600); and a controller, wherein the wireless communication unit is configured to transmit a first foreign object detection status packet and a second foreign object detection status packet to the wireless power transmitter (10, 600), wherein the wireless communication unit is configured to receive a foreign object detection indicator indicating that the foreign object is present in the charging area when the foreign object is present in the charging area based on the first foreign object detection status packet or the foreign object is present in the charging area based on the second foreign object detection status packet and wherein the controller is configured to proceed to a first power transmission procedure when the foreign object is not present in the charging area based on the first foreign object detection status packet and the foreign object is not present in the charging area based on the second foreign object detection status packet, or is configured to proceed to a second power transmission procedure that requests termination of power transmission or proceed to a third power transmission procedure different from the termination of the power transmission when the foreign object is present in the charging area based on the first foreign object detection status packet or the foreign object is present in the charging area based on the second foreign object detection status packet, characterized in that: the first foreign object detection status packet includes a reference quality factor, and the second foreign object detection status packet includes a reference peak frequency, wherein the foreign object detection indicator is determined using a measurement quality factor value of a power signal transmitted from the wireless power transmitter (10, 600) and the reference quality factor of the first foreign object status packet, or determined using a measurement peak frequency of the power signal transmitted from the wireless power transmitter (10, 600) and the reference peak frequency of the second foreign object status packet. the first foreign object detection status packet includes a reference quality factor, and the second foreign object detection status packet includes a reference peak frequency, wherein the foreign object detection indicator is determined using a measurement quality factor value of a power signal transmitted from the wireless power transmitter (10, 600) and the reference quality factor of the first foreign object status packet, or determined using a measurement peak frequency of the power signal transmitted from the wireless power transmitter (10, 600) and the reference peak frequency of the second foreign object status packet.