To achieve a prompt response to a request from a user desiring to improve the environment.

An air conditioning controlling device 12 controlling the volume of a thermal medium that is supplied to an air conditioner through the degree of opening of a control valve, has a room temperature setting value obtaining portion 121 obtaining a room temperature setting value for a controlled area; a supply air temperature measured value obtaining portion 122 obtaining a measured value for a temperature of supply air that is supplied to the controlled area from the air conditioner; a supply air temperature changing portion 124 changing the supply air temperature setting value in accordance with a change in the room temperature setting value; an operating quantity calculating portion 123 calculating an operating quantity based on a deviation between the supply air temperature measured value and the supply air temperature setting value; and an operating quantity output portion 125 outputting an operating quantity to a control valve to control the degree of opening of the control valve.