| Named By: | Ortlam in 1970 |
| Time Period: | Middle Triassic |
| Location: | England - Otter Sandstone Formation. USA, Arizona - Moenkopi Formation (Holbrook Member) |
| Size: | Skull 22 centimetres long, total body length about 1 meter long |
| Diet: | Carnivore/Piscivore |
| Fossil(s): | At least one skull |
| Classification: | | Chordata | Amphibia | Temnospondyli | Mastodonsauroidea | Heylerosauridae | |
| Also known as: | | Moenkopisaurus | Stenotosaurus lehmani | |
Eocyclotosaurus is an extinct genus of mastodonsauroid temnospondyl from the Middle Triassic (Anisian). It measured over 1 metre and had a 22 cm skull.