| Named By: | James Madsen in 1976 |
| Time Period: | Late Jurassic, 155-152 Ma |
| Location: | Utah, Colorado - Morrison Formation |
| Size: | Estimated bertween 5 and 6 meters long, Skull 0.6 meters long |
| Diet: | Carnivore |
| Fossil(s): | At least three individuals with possible further remains |
| Classification: | | Chordata | Reptilia | Dinosauria | Saurischia | Theropoda | Megalosauroidea | |
Marshosaurus is a genus of medium-sized carnivorous theropod dinosaur, belonging to the Megalosauroidea, from the Late Jurassic Morrison Formation of Utah and perhaps Colorado.