The present invention relates to a frame side component of bodywork of a motor vehicle, preferably a car, where, respectively, a metal outer frame manufactured as a single piece and a metal inner frame manufactured as a single piece, where these respectively have at least one aperture delimited by a roof arch segment, a body-floor longitudinal-member segment and a central-column segment, are securely connected to one another, and the cavities produced between metal outer frame and metal inner frame via the connection are reinforced by reinforcement structures composed of moulded-on plastic and the reinforcement structures enter into a secure metal-plastic connection with the two frames.