Manbij plain (Arabic: سهل منبج‎‎ [sæhl ˈmænbid͡ʒ]) is a vast plain on the eastern Aleppo plateau in northern Syria and southeastern Turkey. The plain runs along the western bank of river Euphrates for approximately 140 km from Nizip to Maskanah, with an average width of 15–30 km. It is located within the Manbij and Jarābulus districts of Aleppo Governorate in Syria, and the Nizip and Karkamış districts of Gaziantep Province in Turkey.