| Named By: | Richard Owen in 1884 |
| Time Period: | Late Jurassic, 154-149 Ma |
| Location: | England - Kimmeridge Clay Formation. Possibly also Spain - Terenes Formation |
| Size: | Holotype estimated to be about 5.42 meters long. A second larger individual has been estimated to be about 6.83 meters long |
| Diet: | Carnivore/Piscivore |
| Fossil(s): | Partial skull and postcranial remains of at least two individuals |
| Classification: | | Chordata | Reptilia | Crocodylomorpha | Thalattosuchia | Metriorhynchidae | Geosaurini | |
| Also known as: | | Steneosaurus manselii | |
Plesiosuchus is an extinct genus of geosaurine metriorhynchid crocodyliform known from the Late Jurassic (late Kimmeridgian to early Tithonian stage) of Dorset, England and possibly also Spain. It contains a single species, Plesiosuchus manselii.