The largest-toothed herbivorous dinosaur in the world with tooth upto 14 cm in its 1 meter long lower jaw, known elements are a mandible missing the predentary, isolated maxillary and dentary teeth, cervical and dorsal verts, sternal plates, ribs, and both pubes.

Cladistic analysis recovers a close relationship between L. magnidens and Lurdusaurus arenatus from the Early Cretaceous of Africa. Together, these species represent a previously unrecognized, massively-constructed quadrupedal lineage in the evolution of ornithopod dinosaurs. This discovery also implies a close connection between Eurasia and Africa during the Early Cretaceous. Lanzhousaurus magnidens is different from all other iguanodontians in possessing large individual teeth and a small tooth count per tooth row, with a mere 14, but ~4 cm-wide, tooth families preserved in a single dentary tooth row.