A cooling system for electronic equipment includes an evaporator cooling the electronic equipment, a blower making air heated by the electronic equipment flow into the evaporator, and a condenser condensing a refrigerant to be supplied to the evaporator and also includes a refrigerant liquid pipe guiding a liquefied refrigerant from the condenser to a lower part of the evaporator, a refrigerant gas pipe guiding the refrigerant which evaporates by cooling the electronic equipment from an upper part of the evaporator to the condenser, a refrigerant flow rate control valve controlling a flow rate of the refrigerant flowing into the evaporator, a temperature sensor detecting a temperature of air obtained after passing through the evaporator, and a controller for control valve controlling the control valve on the basis of a detection value of the temperature sensor.