Aresas of Lucania was a Pythagorean philosopher active in the 5th century BCE. He lived in Lucania, a Greek-influenced region of southern Italy, during the Classical period. His identity and era are known from a single ancient source, which lists him among the early followers who preserved the teachings of Pythagoras after the founder's death.

He is credited with writing a treatise titled On Human Nature. This work is now completely lost, surviving only as a title. According to modern scholars, the title suggests it dealt with Pythagorean doctrines concerning the human soul, the body, and principles of health or cosmic harmony, which were central interests of the school.

Aresas's historical importance is minimal but specific. His sole mention confirms he was considered a link in the early chain of Pythagorean tradition. The complete loss of his writing means his individual thought is unknown. He represents one of many minor figures through which the school's ideas were transmitted before the wider philosophical movements of the Hellenistic era.