| Named By: | Richard Owen in 1841 |
| Time Period: | Late Cretaceous, 101-89.3 Ma |
| Location: | England, France and the USA, Texas |
| Size: | Roughly estimated at about 7 meters long |
| Diet: | Carnivore/Piscivore |
| Fossil(s): | Teeth with some jaw material and vertebrae |
| Classification: | | Chordata | Reptilia | Sauropterygia | Plesiosauria | Pliosauroidea | Pliosauridae | |
Polyptychodon (meaning 'shaped fin tooth') is a genus of pliosaurid found Middle-Late Cretaceous marine deposits in southern England. It has been considered a nomen dubium in a 2016 review.