A tank lid (10) comprises: a lid main body (11) which covers an opening portion (4b) of a fuel tank (2), exposing a lid top surface (110) to the outside of the fuel tank; a connector (14) comprising electric drive metal terminals (17) which penetrate through the lid main body (11) from the inside to the outside of the fuel tank (2), and an outside cylinder portion (141) which protrudes from the lid top surface (110) toward the outside of the fuel tank (2), the metal terminals (17) being enclosed by a bottomed cylindrical inner surface (141a) of the outside cylinder portion (141); and an acid-resistant and electrically insulating resin film (15) which is formed as a surface of the outside cylinder portion (141) that is exposed to the outside of the fuel tank (2), on an outside exposed surface (141h) including the bottomed cylindrical inner surface (141a) of the outside cylinder portion (141), and on the lid top surface (110), by dry coating employing chemical vapor deposition.