FUEL CELL STACK

A fuel cell stack including an outside unit disposed outside a cell stacked body and a communicating tube disposed in an exhaust gas flow path to communicate with an upstream and downstream sides of the exhaust gas flow path through a first and second opening. A first and second support portions supporting a first and second end portions on a first and second end sides of the communicating tube are formed in tubular shapes so as to surround the first and second end portions and communicate an internal space of the communicating tube with the exhaust gas flow path. The first and second support portions include tapered portions so that edge portions on outer peripheral surface sides of the first and second end surfaces are capable of abutting on peripheral surfaces of through-holes over a half circumference or longer in a circumferential direction, respectively.