An insulating substrate to which intermediate portions or conductive pastes constituting the intermediate portions are disposed, a front surface protective member to which front surface patterns are formed, and a back surface protective member to which back surface patterns are formed are prepared. A laminated body, to which first end portions or conductive pastes constituting the first end portions are disposed between the intermediate portions or the conductive pastes constituting the intermediate portions and the front surface patterns, and second end portions or conductive pastes constituting the second end portions are disposed between the intermediate portions or the conductive pastes constituting the intermediate portions and the back surface patterns, is constituted. Then, thermoelectric conversion elements are formed by integrating the laminated body.