| Named By: | Harry Govier Seeley in 1874 | 
| Time Period: | Jurassic, 201.6-145.5 Ma[1] | 
| Location: | England - Oxford Clay Formation. France. Greenland, Mexico - La Caja Formation. USA, Wyoming - Sundance Formation | 
| Size: | Up to 6 meters long | 
| Diet: | Piscivore, possibly a specialist in deep water squid | 
| Fossil(s): | Lots of specimens of individuals of all ages which make Ophthalmosaurus one of the best known ichthyosaurs | 
| Classification: | | Chordata | Reptilia | Ichthyosauria | Ophthalmosauridae | Ophthalmosaurinae | | 
| Also known as: | | Apatodontosaurus | Ancanamunia | Baptanodon | Paraophthalmosaurus | Yasykovia | | 
Ophthalmosaurus (meaning "eye lizard" in Greek) is an ichthyosaur of the almost entire Jurassic period (~201.5 to ~145.5 million years ago), named for its extremely large eyes. It had a graceful 6 m (19.5 ft) long dolphin-shaped body, and its almost toothless jaw was well adapted for catching squid. Major fossil finds of this genus have been recorded in Europe and North America.