Jund Qinnasrīn (Arabic: جُـنْـد قِـنَّـسْـرِيْـن, "military district of Qinnasrin") was one of five sub-provinces of Syria under the Umayyad and Abbasid Caliphate, organized soon after the Muslim conquest of Syria in the 7th century CE. Initially, its capital was Qinnasrin, but as the city declined in population and wealth, the capital was moved to Aleppo. By 985, the district's principal towns were Manbij, Iskandarun, Hamah, Shaizar, Ma'arrat al-Numan, Sumaisat, Jusiya, Wadi-Butnam, Rafaniyya, Lajjun, Mar'ash, Qinnasrin, al-Tinah, Balis, and Suwadiyyah.
Originally a part of Jund Hims, the first Umayyad caliph Mu'awiya I established the Jund Qinnasrin when he defeated Hasan ibn Ali, and subsequently detached the people of that area from their allegiance to him. 9th century Muslim historian al-Biladhuri says, however, that it was Muawiya's successor Yazid I who founded the district after separating northern territories from Jund Hims. The newly established district was named after the ancient town of Qinnasrin which was located within its boundaries. Under the Umayyads, Jund Qinnasrin composed of three districts: Antioch, Aleppo, and Manbij.
After caliph al-Mansur's conquests of southern Anatolia, Syria's northern frontiers were considerably extended and in 786, during the reign of the Harun al-Rashid, the now-overgrown Jund Qinnasrin was subdivided. The area toward the northern frontier, comprising the territories of Antioch and the lands east towards Aleppo were split from the district to form Jund al-'Awasim. For the remainder of the Abbasid period, Jund Qinnasrin consisted of the cities of Aleppo (the capital of the district), Qinnasrin and the lands around them, as well as the Sarmin territory.