According to one embodiment, a cooling device includes: a heat transfer unit thermally connected to a mounted first heating element and a mounted second heating element whose mounted height is higher than that of the first heating element, the heat transfer unit including a passage through which a coolant circulates, a heat-receiving section having a first portion thermally connected to the first heating element and a second portion thermally connected to the second heating element, a heat-sinking section that dissipates heat received by the heat-receiving section, a first plate member in which is formed a first groove corresponding to the passage, and a second plate member that covers the first groove. The heat-receiving section is formed at least one of the first and second plate members.