İstanbul Başakşehir Futbol Kulübü (officially known as Medipol Başakşehir Futbol Kulübü for sponsorship reasons), formerly called İstanbul Büyükşehir Belediyespor or Istanbul BB in its abbreviated form, is a Turkishfootball club. They play their home games at the Başakşehir Fatih Terim Stadium in Istanbul and are owned by the Municipality of Istanbul.
The club was founded in 2014. Club's former name was ISKI SK and owned by Municipality's water distribution company. ISKI SK competed in Regional Amateur Football League in 1990–1991 season and promoted to 3rd League. After promotion, the club's name changed to Istanbul BB. The club played in TFF First League until 1996, but after the 2006–2007 season they were promoted to the Turkcell Super League. Finishing 12th in the 2007–2008 season enabled them to remain in the Turkcell Süper Lig for the 2008–2009 season. In the 2009–2010 season, the club finished the season 6th place with a historical success at its own. In the 2012–2013 season, the club finished 16th and relegated to TFF First League. But, it finished 1st League as champions and made immediate return to top level in 2013–14 season. In June 2014, the club's name changed to İstanbul Başakşehir Futbol Kulübü.
On 25 May 2015, İstanbul Başakşehir F.K. signed a sponsorship agreement with Medipol Eğitim ve Sağlık Grubu (Medipol Education and Health Group) for four years and team's name changed to Medipol Başakşehir.