A fuel cell stack preventing deterioration of an end cell, which has a structure for preventing cooling of a neighbor cell adjacent to a closed end plate, is provided. To this end, an open end plate and a closed end plate, which are provided on a first side and a second side, respectively, of the fuel cell stack, fasten a plurality of working cells together. More specifically, a hollow flow space is formed in an inner wall of the closed end plate to form an air pocket therein.