A fuel injection system for internal combustion engines having a multiplicity of injection valves which serves to provide fuel supply is proposed. The fuel injection system includes a common, rigid fuel line, having plug nipples into which the injection valves associated with the individual cylinders of the engine can be inserted in a sealing manner. The fuel line comprises one fuel distributor line and one fuel return flow line located one above the other. Each injection valve has one inlet stub and one outlet stub disposed concentrically relative to one another, protruding into the plug nipple in such a manner that the inflow stub communicates with the fuel distributor line and the outflow stub communicates with the fuel return flow line. As a result, not only is it possible to provide simple sealing toward the outside between the injection valve and the plug nipple but also rapid assembly of the fuel injection system is assured.