Tochisaurus (meaning "Ostrich lizard") is a genus of small troodontid theropod dinosaur from the Late Cretaceous Period of Mongolia.

In 1948, a Soviet-Mongolian expedition found the remains of a small theropod in the Gobi Desert near Nemegt.

In 1987 the find was reported by Sergei Kurzanov and later that year discussed by Halszka Osmólska who suggested it could represent a specimen of the troodontid Borogovia.

The generic name is derived from Mongolian toch', "ostrich", in reference to the fact that the foot, like with that bird, is functionally didactyl, i.e. has only two weight-bearing toes.

[3] Its holotype fossil, PIN 551-224, was found in a layer of the Nemegt Formation, dating from the early Maastrichtian, about 69 million years old.