Eratosthenes was a Greek scholar of the third century BC.

It may also refer to:

• Eratosthenes (crater), a lunar impact crater named after him
• Eratosthenes (statesman), an ancient Athenian statesman of the fifth century BC
• Eratosthenes Seamount
• Eratosthenes of Croton, winner of the Stadion race at the 51st Olympiad in 576 BC