A fuel cell stack induces smooth current collection and liquid or gas flow without using a heavy bipolar plate. The fuel cell stack includes: a membrane and electrode assembly (MEA) in which an electrolyte membrane is disposed between a cathode electrode and an anode electrode; a current collector disposed in the MEA to form an electrical path with an adjacent MEA; and a non-conductive separation plate disposed between the MEA and the adjacent MEA, the non-conductive separation plate forming flow channels to supply a liquid or gas to the cathode electrode and the anode electrode. A fuel cell stack structure having the above structure is simple and lightweight as the MEA includes a thin and lightweight non-conductive polymer separation plate and a current collector to connect adjacent MEAs.