| Named By: | Wang in 1959 |
| Time Period: | Middle Triassic, Anisian |
| Location: | China - Nanchang Province |
| Size: | About 90-100 centimetres long |
| Diet: | Piscivore/Carnivore |
| Fossil(s): | At least one specimen |
| Classification: | | Chordata | Reptilia | Diapsida | |
Nanchangosaurus is an extinct genus of aquatic reptile native to the middle Triassic of China. It was named after the area in China, Nanchang, where it was found. It was about three feet (one meter) in length, and probably fed on fish or used its long jaws to probe for aquatic invertebrates. It resembled the ichthyosaurs in build, and may be related to them.