A fuel cell is formed by stacking an electrolyte electrode assembly and a pair of separators alternately. Each of the separators includes first to third plates. A first cylindrical portion provided at a first small diameter end portion of one separator is inserted into a fuel gas supply passage of the other separator. The first cylindrical portion is subjected to a crimping process such that a joint portion as a predetermined overlapping portion is formed integrally with the one separator and the other separator.