The 1911–12 İstanbul Football League season was the 8th season of the league. Fenerbahçe won the league for the first time. Galatasaray protested Istanbul League Organization' s decision regarding Adnan İbrahim Pirioglu's penalty and did not join the league.
Fenerbahçe, which developed and strengthened its squad with new young players, became champions without being defeated. The most important aspect of this season was that with Fenerbahçe being champions, the championship streak of English and Greek teams completely ended, and from this date on, only Turkish teams became champions in the Istanbul Football League.[1]