Abu Jafar Muhammad ibn Hasan Khazini (900–971) was a Persian Muslim astronomer and mathematician from Khorasan. He worked on both astronomy and number theory. Khazini was one of the scientists brought to the court in Ray, Iran by the ruler of the Buyid dynasty, Adhad ad-Dowleh, who ruled from 949 to 983 AD. In 959/960 Khazini was required by the Vizier of Ray, who was appointed by ad-Dowleh, to measure the obliquity of the ecliptic.