The Gnathorhizidae are an extinct family of lungfish that lived from the late Carboniferous until the middle Triassic.

Gnathorhizid fossils have been found in North America, Madagascar, Australia, and possibly Eastern Europe and South Africa.

Previously, based on morphological evidence, it was assumed that Gnathorhizidae was the sister group to the extant families Lepidosirenidae and Protopteridae, which still live in South America and Africa.

Lungfish teeth attributed to gnathorhizids have been reported from the Lopingian to the Olenekian in Poland and Western Russia.

This suggests gnathorhizids were active predators unlike most lungfish, which feed primarily on benthic invertebrates.