Mansur ibn Yazid ibn Mansur al-Himyari al-Ru'ayni () was an eighth century official for the Abbasid Caliphate.
He was the son of Yazid ibn Mansur, a maternal uncle of the third Abbasid caliph al-Mahdi. In 779 he spent two months as governor of Egypt. Between 781/2 and 783 he was governor of the Yemen, and in 796 he briefly served as the governor of Khurasan.