A fuel cell includes a membrane electrode assembly and first and second metal separators sandwiching the membrane electrode assembly. A first cell voltage terminal for detecting a voltage generated in the membrane electrode assembly is formed integrally with an outer region of the first metal separator. The first cell voltage terminal extends outwardly from the first metal separator. A first seal member covers the outer region of the first metal separator, and includes a first extension seal which covers the first cell voltage terminal to a position near a tip end of the first cell voltage terminal.