A heat control device is provided in a vehicle including a first thermal circuit that circulates a coolant and a second thermal circuit that circulates a refrigerant while changing the state of the refrigerant and is able to exchange heat with the first thermal circuit. When there is a heat discharge request from the second thermal circuit, the heat control device includes a determination unit configured to determine an amount of operation of each of a plurality of units which are used to discharge heat such that the heat discharge request is satisfied and the sum of power consumption values of the plurality of units is minimized.