A fuel rail assembly for an internal combustion engine is disclosed. It comprises a plurality of fuel delivery lines branching off from a fuel rail, each fuel delivery line hydraulically coupling one fuel injector to an outlet port of the fuel rail. Each fuel delivery line has a one-piece pipe which extends from an outlet port of the fuel rail to the respective fuel injector. The pipe has a cylindrical connection section adjoining the respective outlet port and a cylindrical injector cup section in which a fuel inlet portion of the respective fuel injector is received. The connection section and the injector cup section have different hydraulic diameters.