This list of the Paleozoic life of Ohio contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Ohio and are between 538.8 and 252.17 million years of age.
Restoration of the Middle Ordovician-Silurian nautiloid cephalopod Cameroceras feeding on an Aphetoceras, while a quartet of Cyclostomiceras swim by †Cameroceras
†Cardiocarpon
†Cardiomorpha
†Cardiomorpha missouriensis
†Carneyella
†Carneyella foerstei
†Caryocrinites
†Catazone
†Catazone eversolensis – type locality for species