Protoceratops is a sheep-sized, herbivorous ceratopsian dinosaur from the Upper Cretaceous of Mongolia. There are two documented species: the type genus P. andrewsi and the newly named P. hellenikorhinus. Unlike later ceratopsians, it lacked intense horns.

Protoceratops had a big neck frill, which may have served to protect the neck, to anchor jaw muscles, or to make an impression other members of the species. In 1971, A Velociraptor was establishing clutched approximately a Protoceratops in Mongolia. It is believed both died at once while fighting, when they were either astonished by a sand storm or buried when a sand dune misshapen on top of them.

The related protoceratopsian Leptoceratops is known from North America.

Folklorist Adrienne Mayor has optional that skulls of this dinosaur found by ancient peoples may have been at the root of mythical beasts such as the griffin; the horse-like body with the bird-like beak being chiefly notable.