Stefan Janus (22 March 1910 – 11 November 1978), DSO, DFC was a Polish fighter ace of the Polish Air Force in World War II with 6 confirmed kills.

In 1931 he was drafted into army and sent to Volyn Cadet School for Artillery Reserve Officers (Wołyńska Szkoła Podchorążych Rezerwy Artylerii) in Włodzimierz Wołynski.

After his promotion, Janus volunteered for Polish Air Force Academy in Dęblin.

In 1935 he was ordered to the 2nd Air Regiment in Cracow where he flew light bomber and reconnaissance aircraft Breguet 19.

Since October 1938 Janus served as instructor in Air Force Academy.

During the Invasion of Poland Janus was evacuated to Hungary via Romania.

He was interned in Nagykáta but on 26 October he escaped and arrived in France via Yugoslavia and Greece.

One of them spoke fluent German, had a stolen uniform and a fake ID.