A cooling device for a battery that is mounted in a vehicle includes: a cooling fan that is configured to suck air in a vehicle interior, and to blow the sucked air to the battery; an intake air temperature sensor that is configured to detect a temperature of the air sucked by the cooling fan; and an electronic control unit that is configured (i) to control the cooling fan, and (ii) to prohibit the cooling fan from being operated when a detected value of the intake air temperature sensor is lower than a first temperature.