A power transmission device for transmitting electric power to a power reception device in a contactless manner, the power reception device including: a power reception unit including a power reception coil and configured to receive electric power in a contactless manner; a filter connected to the power reception unit a communication unit; a control unit configured to transmit information on the configuration of the filter connected to the power reception unit to the power transmission device through the communication unit of the power reception device; and a protection circuit (325, 375) configured to short-circuit the power reception coil when an overvoltage occurs in the power reception device during power transfer, the power transmission device including: a power transmission unit (220, 240) including a power transmission coil and configured to transmit electric power to the power reception unit in a contactless manner; a filter connected to the power transmission unit (220, 240); a communication unit configured to make wireless communications with the communication unit of the power reception device; and a control unit configured to control the power transmission unit (220, 240) to stop power transmission when a current generated in the power transmission unit (220, 240) exceeds a predetermined threshold value due to short-circuiting of the power reception coil, the control unit is configured to estimate a coupling state between the power transmission coil and the power reception coil, and is configured to change the predetermined threshold value in accordance with the estimated coupling state, characterized in that the control unit is configured to: receive information on the configuration of the filter connected to the power reception unit from the power reception device through the communication unit of the power transmission device; previously store tables associated with combination patterns of the filter connected to the power transmission unit (220, 240) and the filter connected to the power reception unit, each of the tables defining a relation between a coupling state and a predetermined threshold value; select a table from the stored tables, the selected table corresponding to one of the combination patterns of the filter connected to the power transmission unit (220, 240) and the filter connected to the power reception unit; and determine the predetermined threshold value based on the estimated coupling state using the selected table. a power reception unit including a power reception coil and configured to receive electric power in a contactless manner; a filter connected to the power reception unit a communication unit; a control unit configured to transmit information on the configuration of the filter connected to the power reception unit to the power transmission device through the communication unit of the power reception device; and a protection circuit (325, 375) configured to short-circuit the power reception coil when an overvoltage occurs in the power reception device during power transfer, a power transmission unit (220, 240) including a power transmission coil and configured to transmit electric power to the power reception unit in a contactless manner; a filter connected to the power transmission unit (220, 240); a communication unit configured to make wireless communications with the communication unit of the power reception device; and a control unit configured to control the power transmission unit (220, 240) to stop power transmission when a current generated in the power transmission unit (220, 240) exceeds a predetermined threshold value due to short-circuiting of the power reception coil, receive information on the configuration of the filter connected to the power reception unit from the power reception device through the communication unit of the power transmission device; previously store tables associated with combination patterns of the filter connected to the power transmission unit (220, 240) and the filter connected to the power reception unit, each of the tables defining a relation between a coupling state and a predetermined threshold value; select a table from the stored tables, the selected table corresponding to one of the combination patterns of the filter connected to the power transmission unit (220, 240) and the filter connected to the power reception unit; and determine the predetermined threshold value based on the estimated coupling state using the selected table.