| Named By: | Andrews in 1909 |
| Time Period: | Middle Jurassic, Callovian |
| Location: | England and Svalbard |
| Size: | Unavailable |
| Diet: | Piscivore |
| Fossil(s): | Skull and partial post cranial remains |
| Classification: | | Chordata | Reptilia | Sauropterygia | Plesiosauria | Plesiosauroidea | Cryptoclididae | |
Tricleidus is an extinct genus of cryptoclidid plesiosaur known from only specimen (BMNH R3539) from the middle Jurassic of United Kingdom. It was first named by Andrews in 1909 and the type species is Tricleidus seeleyi.