Ataşehir is a modern suburban district of Istanbul, Turkey. It is located at the junction of the O-2 and O-4 motorways in the Anatolian part of Istanbul. Before 2009, the area of present-day Ataşehir was divided between the districts of Kadıköy, Üsküdar, Ümraniye and Kartal. Its neighbours are Ümraniye to the north, Sancaktepe to the northeast, Maltepe to the east, Kadıköy to the south and Üsküdar to the west.

The original housing development of Ataşehir was designed to include 18,000 high-rise condominiums offering luxury residences for 80,000 people with higher incomes. Ataşehir, which hosts the headquarters and offices of numerous companies, is also a business and trading centre. Facilities such as tennis courts, gyms and cinemas make it a popular sports and leisure place. Ataşehir was awarded the Habitat prize.

As of 2006, 8596 housing units were present within the site, housing approximately 35,000 people. New investments still continue on the last empty sites of the district.

As of 2020, the tallest skyscraper in Ataşehir, Istanbul and Turkey is Metropol Istanbul Tower 1 (70 floors, 301 metres tall including its twin spires), which is a mixed-use complex with three towers and a shopping mall.

Unlike in Başakşehir, another satellite city on the west side of Istanbul, no single-family house types were designed for Ataşehir’s residential projects. Most buildings in Ataşehir are high-rise towers, while some of them (especially around the main public squares in the district) are among Istanbul’s and Turkey’s tallest skyscrapers.

Ataşehir can be reached with the M4 line (Kozyatağı station) of the Istanbul Metro.

For private car owners the subdivision is: 10 minutes from the Fatih Sultan Mehmet Bridge; 3 minutes from Highway D-100 and the İzmit-Ankara Trans-European Motorway (TEM); 15 minutes from Bağdat Avenue, the upper-class high street of Kadıköy district; and 20 minutes from Sabiha Gökçen Airport, the second international airport of Istanbul.