A wireless power transmission device is disclosed. The device comprises: a charging pad; and a control unit included in the charging pad and specifying a power transmission group including a plurality of power transmission units for recognizing a wireless power reception device and at least one power transmission unit for transmitting power to the wireless power reception device, wherein the control unit can control a phase of the power transmission group for the wireless power reception device and adjust the power, to be transmitted to the wireless power reception device, of the power transmission group. Therefore, device efficiency can be improved.