A cooling device of the invention includes a flow channel configured so that a coolant passes, a plurality of heat receiving portions configured so that heat generated by a plurality of heat generating portions arranged along one side surface of the flow channel outside the flow channel is transferred, a plurality of heat radiating portions arranged in the flow channel, and a plurality of heat transferring portions configured to connect the heat receiving portions and the heat radiating portions and transfer heat between the heat receiving portions and the heat radiating portions the flow channel is divided into a first flow channel arranged in close proximity to the one side surface and a second flow channel arranged with the first flow channel sandwiched between the one side surface and the second flow channel and the heat radiating portions include one or a plurality of first heat radiating portions arranged in the first flow channel and one or a plurality of second heat radiating portions arranged in the second flow channel.
