Jaʽfar ibn Yahya Barmaki or Jafar al-Barmaki (Persian: جعفر بن یحیی برمکی, Arabic: جعفر بن يحيى, Jaʽfar bin yaḥyā) (767–803), also called Aba-Fadl, was a Persian vizier of the Abbasid caliph Harun al-Rashid, succeeding his father (Yahya ibn Khalid) in that position.

He was a member of the influential Barmakid family, formerly Buddhist leaders of the Nava Vihara monastery.

[1] He was credited with convincing the caliph to open a paper mill in Baghdad, the secret of papermaking having been obtained from Tang Chinese prisoners at the Battle of Talas (in present-day Kyrgyzstan) in 751.

[citation needed] Jaʽfar also appears (under the name of Giafar in most translations) along with Harun al-Rashid in several Arabian Nights tales, often acting as a protagonist.

More recent media inspired by the Arabian Nights has portrayed Jaʽfar as both a villain and a sorcerer: