A preset temperature Ts as a target control temperature of a humidity control device (10) and preset relative humidity Rs as control target humidity are set at an input section (30). An air conditioning control section (42) adjusts the temperature control capacity of the humidity control device (10) so that the temperature in a room approaches the preset temperature Ts. A calculation section (33) calculates target absolute humidity As that is absolute humidity at which the preset relative humidity Rs is achieved at the preset temperature Ts. A humidity conditioning control section (41) adjusts the humidity control capacity of the humidity control device (10) so that the absolute humidity in the room approaches the target absolute humidity As.
