To provide a heat spreader easily manufacturable at low cost, providing excellent heat transport efficiency, and providing excellent reliability.

For example, two heat pipes 1a and 1b arranged parallel with each other are spirally wound generally without a clearance, and adjacent heat pipes 1a and 1b are fixed to each other to form in a panel shape. A flat plate 2 of a heat conductive member is installed on both of the front and rear surfaces of the panel formed of the heat pipes 1a and 1b. Thus a heat diffusion is efficiently performed by performing not only the heat transfer of the heat pipes 1a and 1b in the longitudinal direction but also a heat transfer between the adjacent heat pipes 1 and 1b.