The present application provides a wireless power transmission device and a foreign object detection method thereof. The method includes: acquiring an input current of a transmitting unit of the wireless power transmission device and a temperature of a transmitting coil in the transmitting unit; determining a first current reference value according to the temperature of the transmitting coil; and determining a foreign object detection result according to the input current and the first current reference value corresponding to the temperature of the transmitting coil. By detecting the input current of the transmitting unit of the wireless power transmission device, it is determined whether there is a foreign object in a transmission space of the wireless power transmission device. Moreover, a temperature detection unit is added, and adjustment is made to a current threshold according to the temperature of the coil, thereby achieving more accurate foreign object detection.