A separator for a fuel cell includes a metal plate which defines a passage and a manifold, frames having gaskets which are integrated therewith using injection, and a bonding unit for bonding the frames to the metal plate. The gaskets may be differently formed. This resolves process interference problems between conductive surface treatment and gasket cross-linking, obviates deburring of the gasket, and preventes poor injection of the gaskets, which ensures stable quality of the separator, increases productivity and decreases the manufacturing cost.