Royal Prussian Jagdstaffel 9 was a "hunting group" (fighter squadron) of the Luftstreitkräfte, the air arm of the Imperial German Army during World War I.

Although the squadron, and the Luftstreitkräfte, were short-lived, they had great influence on the Nazi Luftwaffe, as can be seen by the later careers of the unit's Staffelführer.

In turn, it had suffered thirteen pilots killed in combat, three wounded, five non-combat deaths, and three injuries.

The unit was officially founded five days later; it mobilized a week later, and moved to Leffincourt.

Other pilots, such as Hartmuth Baldamus, Fritz Pütter, Erich Thomas, Hermann Pfeiffer, and Heinrich Kroll also served with distinction.