Clinias of Tarentum was a Pythagorean philosopher from the Greek city of Tarentum in southern Italy, active during the 5th and 4th centuries BCE. This was a period when Pythagoreanism was a major intellectual and political force in the region. He was a contemporary and associate of other famous Pythagoreans, including Philolaus of Croton and the statesman Archytas, also from Tarentum.

No writings by Clinias survive today. He is known only through later accounts that record stories about his life and character. According to the later philosopher Iamblichus, Clinias was celebrated for his deep piety and moral integrity. A famous anecdote describes how he spent a large fortune to save his friend Damon from execution, an act presented as embodying the core Pythagorean virtues of loyalty and friendship.

Modern scholars see Clinias as a representative figure of middle Pythagoreanism. His significance lies less in specific philosophical doctrines—none are securely attributed to him—and more in his role within the tradition. His recorded life served as a moral example, illustrating how Pythagorean ethical ideals were put into practice. His connections to major figures like Philolaus and Archytas also place him within the important network that preserved and developed Pythagorean thought during the Classical period.