A loop-type heat pipe comprising: an evaporator that vaporizes a working fluid; a condenser that liquefies the working fluid; a liquid pipe by which the evaporator and the condenser are connected to each other; and a vapor pipe by which the evaporator and the condenser are connected to each other, wherein the vapor pipe and the liquid pipe form a loop, wherein the evaporator is formed by layered metal layers (61 to 66) and the layered metal layers (61 to 66) forming the evaporator comprise: a first outermost metal layer positioned on one outer side in a layering direction of the layered metal layers; a second outermost metal layer positioned on the other outer side opposite to the one outer side in the layering direction; and an inner layer (62 to 65) positioned between the first outermost metal layer and the second outermost metal layer , wherein the inner layer (62 to 65) comprises: a first metal layer adjacent to the first outermost metal layer ; and a second metal layer adjacent to the second outermost metal layer , wherein at least one space where vapor generated by vaporizing the working fluid flows and a porous member that communicates with the at least one space are provided in the inner layer (62 to 65), characterized in that the first metal layer is formed with a first bottomed groove opened to a side of the second metal layer , and the second metal layer is formed with a second bottomed groove opened to a side of the first metal layer side , wherein one end of the space in the layering direction is closed by a portion of the first metal layer where the first bottomed groove is formed, and the other end of the space in the layering direction is closed by a portion of the second metal layer where the second bottomed groove is formed. an evaporator that vaporizes a working fluid; a condenser that liquefies the working fluid; a liquid pipe by which the evaporator and the condenser are connected to each other; and a vapor pipe by which the evaporator and the condenser are connected to each other, wherein the vapor pipe and the liquid pipe form a loop, wherein the evaporator is formed by layered metal layers (61 to 66) and the layered metal layers (61 to 66) forming the evaporator comprise: a first outermost metal layer positioned on one outer side in a layering direction of the layered metal layers; a second outermost metal layer positioned on the other outer side opposite to the one outer side in the layering direction; and an inner layer (62 to 65) positioned between the first outermost metal layer and the second outermost metal layer , wherein the inner layer (62 to 65) comprises: a first outermost metal layer positioned on one outer side in a layering direction of the layered metal layers; a second outermost metal layer positioned on the other outer side opposite to the one outer side in the layering direction; and an inner layer (62 to 65) positioned between the first outermost metal layer and the second outermost metal layer , wherein the inner layer (62 to 65) comprises: a first metal layer adjacent to the first outermost metal layer ; and a second metal layer adjacent to the second outermost metal layer , wherein at least one space where vapor generated by vaporizing the working fluid flows and a porous member that communicates with the at least one space are provided in the inner layer (62 to 65), characterized in that the first metal layer is formed with a first bottomed groove opened to a side of the second metal layer , and the second metal layer is formed with a second bottomed groove opened to a side of the first metal layer side , wherein one end of the space in the layering direction is closed by a portion of the first metal layer where the first bottomed groove is formed, and the other end of the space in the layering direction is closed by a portion of the second metal layer where the second bottomed groove is formed. <EOS>