Disclosed is an internal current collection structure of a tubular thermal to electric converting cell including an internal electrode, a solid electrolyte and an external electrode. The internal current collection structure includes: a first current collector which closely contacts with the internal electrode of the tubular thermal to electric converting cell; a second current collector which fixes the first porous current collector to the inside of the tubular thermal to electric converting cell and causes the first current collector to be in close contact with the internal electrode; and a lead wire which is a conductive medium and is located between the first current collector and the second current collector.