A loop heat pipe includes an evaporator configured to evaporate a liquid phase working fluid to generate vapor, the evaporator including first and second inner surfaces that face each other; a comb-like porous body including a plurality of comb teeth, the comb-like porous body being disposed inside the evaporator; a plurality of grooves disposed on one of the first inner surface and second inner surface so as to overlap the plurality of comb teeth; a vapor transport line configured to transport the vapor of the working fluid; a condenser configured to liquefy the vapor of the working fluid; and a liquid transport line configured to transport the liquified vapor as a liquid phase working fluid, wherein each of the liquid transport line and the vapor transport line connects the evaporator and the condenser, such that the vapor transport line and the liquid transport line form a loop-like flow passage.