To provide a heat pipe apparatus, and its manufacturing method and quality estimation method capable of preventing production of a defective article and of easily achieving quality estimation.

A manufacturing method for a heat pipe apparatus is constructed such that a plurality of heat pipes 5 in contact with each other are disposed between a surface member 2 and a back surface member 3, and then a caking member is filled in the heat pipe, and the heat pipes are covered with the caking member to form the same into a film. In the method, an outer cylinder of the heat pipe 5 is formed with conductive plastic. These heat pipes are disposed between the surface member and the back surface member such that they are brought into contact with each other, and then electric resistance between the adjacent heat pipes is measured. When a measured value is a predetermined value or less, a caking material is filled between the surface member and the back surface member and is formed into a film.