| Named By: | Jaci Antonio Louzada Tupi Caldas in 1936 |
| Time Period: | Middle Triassic-Late Triassic |
| Location: | Argentina, Brazil and Germany |
| Size: | Up to 2.4 meters long |
| Diet: | Herbivore |
| Fossil(s): | Many individuals, including remains of juveniles |
| Classification: | | Chordata | Synapsida | Therapsida | Anomodontia | Dicynodontia | Kannemeyeriidae | |
| Also known as: | | Dinodontosaurus oliveirai | |
Dinodontosaurus (meaning "terrible-toothed lizard") is a genus of dicynodont therapsid. It was one of the largest herbivores of the Triassic (about 2.4 m long and weighing a few hundred pounds) and had a beak corneum. It lived in the Middle Triassic but disappeared in the Upper Triassic.