A spinning nozzle for an air-jet spinning machine has a base body with an internal turbulence chamber, an inlet opening for the fiber sliver which enters the turbulence chamber and a fiber guide channel for guiding the fiber sliver entering the inlet opening. A thread-forming element extends at least partially into the turbulence chamber and has an inlet mouth as well as an adjoining take-off channel for the thread in the transport direction. Air nozzles are directed into the turbulence chamber. The spinning nozzle has an extension piece that is releasably fixed to the base body in the region of the inlet opening, wherein the fiber guide channel adjoining the inlet opening is formed at least partially by a channel section of the extension piece.