An air-conditioning system comprising: an air conditioner including: an outlet for conditioned air, the outlet being disposed at a panel body and opened downward; a louver that is pivotally provided at the outlet and configured to adjust a blow-out direction of the conditioned air; an plate-shaped member for providing an anti-draft function, that is disposed on the outside of the outlet of the panel body and is pivotable between a withdrawn position flush with the panel body and a louver-direction position facing the conditioned air blown out from the outlet; and a pivot mechanism that is configured to cause the plate-shaped member to pivot between the two positions; the air-conditioning system being characterized in that it comprises a control device that is configured to control the air conditioner, the control device comprising: a storage unit that is configured to store correspondence information for linking positional information on the louver to positional information on the plate-shaped member that is configured to block the conditioned air and change a wind direction of the conditioned air blown out from a position of the louver; and a control unit that is configured to determine a position of the plate-shaped member corresponding to a current position of the louver based on the correspondence information, and cause the plate-shaped member to move to the determined position. an air conditioner including: an outlet for conditioned air, the outlet being disposed at a panel body and opened downward; a louver that is pivotally provided at the outlet and configured to adjust a blow-out direction of the conditioned air; an plate-shaped member for providing an anti-draft function, that is disposed on the outside of the outlet of the panel body and is pivotable between a withdrawn position flush with the panel body and a louver-direction position facing the conditioned air blown out from the outlet; and a pivot mechanism that is configured to cause the plate-shaped member to pivot between the two positions; the air-conditioning system being characterized in that it comprises a control device that is configured to control the air conditioner, the control device comprising: a storage unit that is configured to store correspondence information for linking positional information on the louver to positional information on the plate-shaped member that is configured to block the conditioned air and change a wind direction of the conditioned air blown out from a position of the louver; and a control unit that is configured to determine a position of the plate-shaped member corresponding to a current position of the louver based on the correspondence information, and cause the plate-shaped member to move to the determined position. a storage unit that is configured to store correspondence information for linking positional information on the louver to positional information on the plate-shaped member that is configured to block the conditioned air and change a wind direction of the conditioned air blown out from a position of the louver; and a control unit that is configured to determine a position of the plate-shaped member corresponding to a current position of the louver based on the correspondence information, and cause the plate-shaped member to move to the determined position.