Estemmenosuchus (meaning "crowned crocodile" in Greek) is an extinct genus of large, early omnivorous therapsid.

[2] Its skull was long and massive, up to 65 cm (26 in) in length,[2] and possessed several sets of large horns, somewhat similar to the antlers of a moose, growing upward and outward from the sides and top of the head.

Two species have been identified, from the Ocher Assemblage Zone Belebei Formation at the Ezhovo locality near Ochyor in the Perm region of the Russia in 1960.

They were found with the Biarmosuchians Eotitanosuchus olsoni and Biarmosuchus tener in channel flood deposits of the young Ural Mountains.

Its large size and compact build gave a small surface-to-volume ratio and suggests it would not gain (or lose) temperature quickly.