Jabala ibn al-Ayham (Arabic: جبلة بن الأيهم) was the last ruler, or phylarch, of the Ghassanid dynasty in Syria in the 7th century. He commanded Arab Christian tribal contingents on behalf of the Byzantine Empire against Arab Muslim forces during the Muslim conquest of Syria in the 630s.
In the battles of Dumat al-Jandal in northern Arabia and the decisive battle of Yarmuk in southern Syria in 636, his forces were defeated. He supposedly converted to Islam, before breaking ties with the faith in protest to indignities he consequently suffered related to Islamic egalitarian principles. Afterward, he left Syria permanently, taking refuge with his tribesmen in Byzantine Anatolia. Historians are divided on the historicity of Jabala due the lack of contemporary source material, with some arguing his personality was essentially a literary device of later Islamic writers.