Quasicolognathus () is an extinct genus of enigmatic reptile known from the Middle Triassic Erfurt Formation of Germany. The genus contains a single species, Quasicolognathus eothen, known from a fragmentary skull and isolated mandibles. These bones exhibit striking similarities to Colognathus obscurus, a species known from the Norian of the United States. The Quasicolognathus lower jaw material was initially described in 2011 as a , and later assigned to Colognathus in 2013 before the eventual discovery of additional skull bones. More detailed analyses of the German fossils allowed them to be described as belonging to a distinct taxon in 2022. These two genera are placed in their own family, Colognathidae, which has uncertain relationships to other reptiles.