Abdullah Mucib Avcı (born 31 July 1963) (Turkish pronunciation: , born 5 April 1965) is a Turkish former footballer and is currently the manager of Beşiktaş. He has also managed the Turkish national team.
Avcı played for Vefa, Fatih Karagümrük, Çaykur Rizespor, Kahramanmaraşspor, Bakırköyspor, Kasımpaşa, İstanbulspor, Küçükçekmece, Nişantaşıspor respectively and retired in 1999 at the club where he started football. Avcı's coaching career began at İstanbulspor in 1999 as assistant coach before a spell as Galatasaray youth academy chief.
He took over Turkish U17 national football team leading them to the 2005 UEFA European Under-17 Football Championship gold medal and 4th place at the FIFA Youth-World championship in Peru. With stars like Nuri Şahin, Deniz Yılmaz, and Tevfik Köse, Abdullah Avcı was confident of success. In August 2006 he moved to İstanbul Büyükşehir Belediyespor, leading them to promotion in his first season and keeping them in the Süper Lig ever since. After the 2006–07 season they were promoted to the Süper Lig. Finishing 12th in the 2007–08 season enabled them to remain in the Süper Lig for the 2008–09 season. In the 2009–10 season, the club finished the season 6th place with a historical success at its own.