A loop heat pipe includes: an evaporator configured to evaporate working fluid; a condenser configured to condense the working fluid; a liquid pipe which connects the evaporator and the condenser and has a first pipe wall and a second pipe wall which is opposed to the first pipe wall; a porous body which is provided in the liquid pipe and is configured to guide the working fluid condensed by the condenser to the evaporator; a flow channel which is a space that is formed in the liquid pipe and guides the working fluid condensed by the condenser to the evaporator; and a vapor pipe which connects the evaporator and the condenser and forms a loop together with the liquid pipe. The porous body is disposed to be in contact with the first pipe wall.