Yahya ibn Abi Mansur (Arabic: یحیی ابن ابی منصور), was a senior Persian official from the Banu al-Munajjim family, who served as an astronomer/astrologer at the court of Abbasid caliph al-Ma'mun. His Persian name was Bizist, son of Firuzan (بزیست فیروزان). Since his father Abu Mansur Aban was an astrologer in service of caliph al-Mansur, it can be concluded that Yahya spent his childhood in Baghdad. His first known position was as an astrologer for al-Fadl ibn Sahl, vizier of the caliph al-Ma'mun. After the assassination of al-Fadl, Yahya converted to Islam and adopted his Arabic name. He was also associated with the House of Wisdom and is mentioned as a teacher of the Banu Musa. He died near Aleppo in 830 CE.