A solid electrolyte fuel battery having a fuel gas supply channel that is composed of a first anode gas supply channel part, at least a part of an inner wall surface of which is a fuel electrode layer, and a second anode gas supply channel part; and an air supply channel that is composed of a first cathode gas supply channel part, at least a part of an inner wall surface of which is an air electrode layer, and a second cathode gas supply channel part. The cross-section area of the first anode gas supply channel part is larger than the cross-section area of at least a portion of the second anode gas supply channel part. The cross-section area of the first cathode gas supply channel part is larger than the cross-section area of at least a portion of the second cathode gas supply channel part.