Hanssuesia is a genus of pachycephalosaurid dinosaur from the Late Cretaceous period. It lived in what is now Alberta and Montana. Like other pachycephalosaurs, Hanssuesia had a thick skull roof. However, Hanssuesia is distinguished from other pachycephalosaurs by having a depressed parietal region, wide frontoparietal dome, broad nasal characteristics, reduced prefontal lobes, and a reduced parietosquamosal shelf.