A loop heat pipe includes: an evaporator; a condenser; a liquid pipe; a vapor pipe; and a loop-like flow channel through which the working fluid flows. At least one of the evaporator, the condenser, the liquid pipe, and the vapor pipe includes a first outer metal layer, a second outer metal layer, and an inner metal layer. The inner metal layer includes a porous body. The porous body includes: a first bottomed hole formed in one face of the inner metal layer; a second bottomed hole formed in the other face of the inner metal layer; a pore, wherein the first bottomed hole and the second bottomed hole partially communicates with each other through the pore; and a first column portion provided inside the first bottomed hole. The first column portion is bonded to the first outer metal layer.