Polyclitus' two greatest statues were the Diadumenus (430 BC; “Man Tying on a Fillet”) and the Doryphorus (c. 450–440 BC; “Spear Bearer”), the latter work being known as the Canon (Greek: Kanon) because it was the illustration of his book by that name. The Canon is a theoretical work that discusses ideal mathematical proportions for the parts of the human body and proposes for sculpture of the human figure a dynamic counterbalance—between the relaxed and tensed body parts and between the directions in which the parts move. In Greece this concept was called symmetria, and Polyclitus' statues of young athletes, balanced, rhythmical, and finely detailed, were the best demonstration of his principles. His freer use of contrapposto (depiction of the human body with twistings in its vertical axis) helped liberate Greek sculpture from its tradition of rigid frontal poses.

Another outstanding work by Polyclitus was his gold and ivory statue of the goddess Hera. As a contemporary of Phidias, Polyclitus was considered by the Greeks of the period to be that sculptor's equal. His Hera was ranked with Phidias' gold and ivory statues of Athena and Zeus, and Polyclitus' entry in a competition to make an Amazon for the Temple of Artemis at Ephesos was selected over that of Phidias, among others. None of Polyclitus' original works survive, and the Doryphorus and Diadumenus are known only through Roman copies.