| Named By: | Gideon Mantell in 1828 |
| Time Period: | Early Cretaceous |
| Location: | England, Sussex |
| Size: | In the past estimated about 4 meters long, but given the severe lack of fossils this is highly speculative |
| Diet: | Herbivore |
| Fossil(s): | Partial right mandible (lower jaw) |
| Classification: | | Chordata | Reptilia | Dinosauria | Ornithischia | Thyreophora | Stegosauria | Huayangosauridae | |
Regnosaurus (meaning "Sussex lizard") is a genus of herbivorous stegosaurian dinosaur that lived during the Early Cretaceous Period in what is now England.