In a heat spreading module, a plurality of hollow paths is formed in a thin plate-shaped main body so as to pass though the heating portion, and the hollow paths communicate with each other in a heating portion, a working fluid is enclosed in the hollow paths, a wick is disposed in each of the hollow paths such that a vapor flow path in which vapor of the working fluid flows is formed in each of the hollow paths, a part of each wick is positioned at the heating portion, and the vapor flow paths formed in the hollow paths communicate with each other in the heating portion.