Abdallah ibn Khazim () was a son of the famed Khurasani Arab general Khazim ibn Khuzayma al-Tamimi and a senior official in the Abbasid Caliphate. Khuzayma was the son of Khazim ibn Khuzayma, a Khurasani Arab who became an early follower of the Abbasids and played an instrumental rule in their rise to power both during and after the Abbasid Revolution. Through Khazim, the family achieved a prominent place among the Khurasaniyya, the Khurasani soldiers who had come west during the Revolution and formed the main power-base of the early Abbasid regime. Abdallah served as chief of security (sahib al-shurta) for the Caliph al-Mahdi (r. 775–785) in 781 CE, for al-Mahdi's son and heir-apparent al-Hadi (r. 785–786) during his campaign in Jurjan. Caliph Harun al-Rashid (r. 786–809) appointed him go