Examples of a cooling system include a flow channel through which a cooling medium flows, a valve that is provided in the flow channel and configured to adjusts a flow rate of the cooling medium, a thermometer for measuring temperature of the cooling medium, a flowmeter for measuring a flow rate of the cooling medium passing through the valve, and a controller for determining cooling capacity of the cooling medium from measurement results of the thermometer and the flowmeter, and adjusting the valve so that the cooling capacity of the cooling medium approaches to a target value when the determined cooling capacity is different from the target value.