Known fuel injectors have a valve-closure member, which cooperates with a sealing seat of a valve seat, and a flow exit region situated downstream from the sealing seat, the fuel spray generated by the fuel injectors having an average droplet diameter that is not small enough for future regulations governing exhaust emission. In the fuel injector according to the present invention the atomization is improved in a simple manner and the average droplet diameter is reduced without additional auxiliary power. The projections which influence the fuel flow are situated in the flow exit region.