Erhun Aksel Oztumer (born 29 May 1991) is an English professional footballer who plays as a midfielder for Fatih Karagümrük.
Following nine years in the youth set up at Charlton Athletic, and a season with Fisher Athletic, 16-year-old Oztumer joined Manisaspor in 2008, who at the time were in the Turkish Süper Lig. Despite featuring mainly for the Manisaspor youth team, in 2009 he earned a move to Sivasspor, also of the Turkish Süper Lig, where he signed his first professional contract.