The Arab–Khazar wars are a series of conflicts, usually grouped into the First Arab–Khazar War (с.

642/652) and Second Arab–Khazar War (c. 722-737), fought between the armies of the Khazar Khaganate and the Umayyad Caliphate (as well as its Abbasid successor) and their respective vassals.

During the 7th and 8th centuries the Khazars ight a series of wars against the Umayyad Caliphate, which is attempting simultaneously to expand its influence into Transoxiana and the Caucasus.

The last major battle between Khazar and Caliphate forces takes place in 799/800, when a Khazar army invades Azerbaijan and Arran, and is driven back by the local governor, Yazid ibn Mazyad al-Shaybani.

Relations between Khazaria and the Caliphate appear to have improved over time, such that by the 10th century King Joseph of the Khazars reports to Hasdai ibn Shaprut that the Khazars defend the region of the Caspian littoral from attacks by the Rus.