Polybius (c. 203 BC – 120 BC) was an ancient Greek historian.
Polybius may also refer to:
People Polybius (freedman) (fl. 1st century), freedman and later secretariat under the Roman Emperor Claudius Polybius of Tralles, a 2nd-century Christian bishop mentioned in the writings of Ignatius of Antioch
Other uses Polybius (crab), a genus of swimming crabs Polybius (crater), a lunar impact crater Polybius (urban legend), a fictitious video game featured in urban legend Polybius (2017 video game), released for the PlayStation 4 Polybius square, a cipher key technique "Polybius", the fourth episode of Dimension 404, based on the urban legend Polybius Bank, an Estonian bank
See also Polybus (disambiguation)