Tusi, philosopher, theologian, mathematician, astrologer and astronomer, is by far the most celebrated scholar of the 13th century in eastern Islamic lands. When his land was conquered by the Mongols, he joined Hulagu's service. Hulagu Khan was deeply impressed by his knowledge and astrological competency. Tusi established the observatory at Maragha and produced new astronomical tables called "Al-Zij-Ilkhani." His books on astrology remained unknown till today. At this presentation we will meet Tusi and his astrology books.