[1] Hazhenia belongs to a group of therocephalians called Baurioidea and possesses many mammal-like features such as cusped teeth and a secondary palate, both of which evolved independently in baurioids.

[2] Hazhenia is known from a single skull that was discovered by a group from the Institute of Vertebrate Paleontology and Paleoanthropology in 1977, a year after the discovery of the first Ordosiodon remains.

[3] Both were initially classified as members of Scaloposauria, a group of small-sized therocephalians now regarded as a paraphyletic assemblage of basal baurioids.

A phylogenetic analysis of therocephalians published in 2014 found Hazhenia and Ordosiodon to be each other's closest relatives, and placed both in a derived position within Baurioidea, close to the family Bauriidae.

Below is a cladogram from that analysis:[4] Lycosuchus vanderrieti Scylacosauridae Scylacosuchus orenburgensis Perplexisaurus foveatus Chthonosauridae Akidnognathidae Hofmeyriidae Whaitsiidae Ictidosuchops rubidgei Ictidosuchidae Regisauridae Karenitidae Lycideopidae Scaloposaurus constrictus Ericiolacertidae Nothogomphodon danilovi Hazhenia concava Ordosiodon youngi Bauria cynops Antecosuchus ochevi Microgomphodon oligocynus Traversodontoides wangwuensis