A cooler includes an evaporator and a condenser. The evaporator includes a housing, a wick, and a groove member having a plurality of vapor flow channels through which working fluid changed in phase from a liquid phase to a gas phase flows, the groove member being coupled to the wick. The housing includes a heat receiver to which the heat is transferred from a cooling target. The groove member includes a plurality of plate-like members, arranged side by side along a predetermined direction, and constituting the plurality of vapor flow channels. Each of the plate-like members includes a bent part formed by bending a part of the plate-like member, the bent part being coupled to the heat receiver.