A composite member includes a metal sheet having a bent portion formed by bending, and a resin member joined to at least a part of the bent portion. The metal sheet includes an opening provided on an inner side of the bent portion, and a tapered recess that tapers off from an outer side of the bent portion toward the opening. The resin member includes an inner resin part filled in the recess, and an exposed resin part provided to be continuous with the inner resin part and to extend to an inner surface of the bent portion through an edge portion of the opening.