A cooling device includes a duct with one opened end and another opened end; a fan disposed inside the duct, the fan being configured to send air present inside the duct in an air-sending direction; a heat sink disposed outside the duct, the heat sink including a base part having an opposed surface opposed to a mouth of the another end of the duct, and heat-sink fins including a plurality of thin plates extending from the opposed surface along the air-sending direction; a heat source in contact with the base part; a heat pipe connected to the heat source or the heat sink; and heat-pipe fins disposed between the fan and the one end of the duct inside the duct, the heat-pipe fins including a plurality of thin plates extending from the heat pipe along the air-sending direction.