Abstract: The invention concerns a single-block fuel injection rail. The rail according to the invention comprises at least one rectilinear hollow tube, to which are joined at least one fuel intake tip, at least one injection intake and rail fastening means. The rail is formed from a metal billet placed in a die and has a longitudinal solid primary shape having transverse branches whose axes are perpendicular to the longitudinal axes of the primary form. The rail is cooled and machined so as to give it its final shape.