Nikkasaurus is an extinct genus of therapsids first named and described by Ivakhnenko.

Nikkasaurus, named after Russian paleontologist Nikolay Kalandadze, was a small therapsid, with a skull about 5 cm long.

The eyes had large orbits and sclerotic rings, and the head was tilted back, as with all therapsids.

The skull looks superficially similar to those of the pelycosaurs, in particular members of Varanopidae.

Nikkasaurus is possibly a relic of a more ancient stage of therapsid development.