Metriorhynchids were a clade of fully-aquatic crocodylomorphs that lived in seas of the Jurassic and Cretaceous periods. Their fore-legs were reduced and paddle-like, and unlike living crocodilians, they lost their osteoderms ("armour scutes"). Their body shape maximised hydrodynamy (swimming efficiency), as did having a shark-like tail fin.

Metriorhynchids were the only group of archosaurs to become fully adapted to the marine realm, becoming pelagic in lifestyle.

The type genus for Metiorhynchidae is Metriorhynchus from the Middle to Late Jurassic. Other genera included within this family are Teleidosaurus, Geosaurus, Dakosaurus and Enaliosuchus.