Separator

A separator that is formed in a plate shape, constitutes a fuel cell, and is disposed so as to be adjacent to an electrolyte membrane to which fuel gas and oxidation gas are fed, the separator comprising:

• an anode separator including a fuel gas flow passage surface on which a flow path of the fuel gas is formed;
• a cathode separator including an oxidation gas flow passage surface on which a flow path of the oxidation gas is formed;
• a joint portion that extends so as to surround the flow path of the fuel gas and the flow path of the oxidation gas, and joins the anode separator and the cathode separator to each other;
• and
• a seal portion provided on at least one of the fuel gas flow passage surface and the oxidation gas flow passage surface, extending along the joint portion, and formed so as to overlap the joint portion when viewed in a thickness direction of the separator.