| Named By: | Reuss in 1855 |
| Time Period: | Cretaceous |
| Location: | Czech Republic |
| Size: | Unavailable |
| Diet: | Piscivore |
| Fossil(s): | Uncertain |
| Classification: | | Chordata | Reptilia | Sauropterygia | Plesiosauria | |
Aptychodon (meaning "unwrinkled tooth") is an extinct genus of plesiosaur from the Cretaceous of what is now the Czech Republic. The genus was named by Reuss in 1855.