Abū ʿAbd Allāh al-Mufaḍḍal ibn ʿUmar al-Juʿfī (Arabic: أبو عبد الله المفضل بن عمر الجعفي), died before 799, was an early Shi'i leader and contemporary of the Imams Ja'far al-Sadiq (c. 700–765) and Musa al-Kazim (745–799). He belonged to those circles in Kufa (Iraq) whom later Twelver Shi'i authors would call ghulāt ('exaggerators', singular ghālin) for their 'exaggerated' veneration of the Imams.