A wireless power transmitter for transmitting power to a wireless power receiver, including a controller configured to determine whether a foreign object is present in a charging area of the wireless power transmitter; and a transmission part configured to transmit wireless power according to whether the foreign object is present, wherein the controller receives a signal including an FOD status packet from the wireless power receiver, and determines whether the foreign object is present in the charging area of the wireless power transmitter based on the FOD status packet; wherein the controller is set to be operated in a first power transfer mode when determining that the foreign object is present in the charging area, or to be operated in a second power transfer mode when determining that the foreign object is not present in the charging area; and wherein the controller determines whether the foreign object is present in the charging area based on information other than information included in the FOD status packet, while being operated in any one of the first power transfer mode and the second power transfer mode.