Ubayd-Allah ibn Jahsh (Arabic: عبيد الله بن جحش) (c.588-627) was one of the four monotheistic hanifs mentioned by Ibn Ishaq, the others being Waraqah ibn Nawfal, Uthman ibn Huwarith and Zayd ibn Amr.
He was the son of Jahsh ibn Riyab and Umama bint Abdulmuttalib, hence a brother of Abd-Allah ibn Jahsh, Zaynab bint Jahsh, Abu Ahmad ibn Jahsh, Habiba bint Jahsh and Hammanah bint Jahsh, a first cousin of Islamic prophet Muhammad and Ali, and a nephew of Hamza ibn ‘Abd al-Muttalib. He married Ramlah bint Abi Sufyan (who was also known as Umm Habiba), and they had one daughter, Habibah bint Ubayd-Allah.
He and his wife became Muslims and, in order to escape from the Meccan persecution, they emigrated to Abyssinia. At Axum, part of the Aksumite Empire the Christian king, Aṣḥama ibn Abjar, gave sanctuary to the Muslims. There Ubayd-Allah eventually converted to Christianity and testified his new faith to the other Muslim refugees. Ibn Ishaq relates: