Autolycus of Pitane was a Greek astronomer and mathematician active in the late 4th century BCE, making him a contemporary of Euclid. He is among the earliest Greek mathematical astronomers whose complete works survive. His writings reflect a stage of astronomy prior to the advanced spherical developments of later Hellenistic scholars.

His two extant treatises are On the Moving Sphere, the oldest surviving Greek mathematical treatise, and On Risings and Settings.

Autolycus holds major significance as the author of the earliest complete Greek mathematical texts. His works are foundational in spherical astronomy, systematically detailing the geometry of the celestial sphere and stellar phenomena through a deductive approach. They served as standard textbooks, forming part of the "Little Astronomy" curriculum, and were studied by later figures like Pappus of Alexandria, providing crucial insight into pre-Hellenistic astronomical theory.