Ali ibn Mu?ammad ibn al-Hadi (Arabic: ?????? ???? ???????? ???????????; 829 – 868 CE) was the tenth of the Twelve Imams after his father Muhammad al-Jawad and before his son Hasan al-Askari.
He remained in Medina teaching until the age of 30 when he was summoned to Samarra by the Abbasid caliph Al-Mutawakkil.
There he was treated roughly by the caliph and his successors until, according to Shiite accounts, he was poisoned through intrigue of Al-Mu'tazz the Abbasid caliph, in 254/868, and was buried in Samarra.
He is commonly referred to by the title al-Hadi (the one who shows right path) and Ali an-Naqi.