Tricuspisaurus is an extinct genus of trilophosaur. Fossils are known from the Ruthen Quarry in Glamorgan, Wales. Like some other trilophosaurs, it has an edentulous, or toothless beak. Tricuspisaurus gets its name from its heterodont dentition, which includes tricuspid teeth, or teeth with three cusps. The type species, T. thomasi, was named in 1957 along with the closely related trilophosaur Variodens inopinatus from Somerset, England.