| Named By: | Ronald S. Tyloski, Timothy B. Rowe, Richard A. Ketcham and Matthew W. Colbert in 2002 |
| Time Period: | Early Jurassic, 196.5 Ma |
| Location: | USA - Arizona/Navajo Nation - Kayenta Formation |
| Size: | Skull around 38 centimetres long. Total length unknown due to lack of post cranial remains |
| Diet: | Carnivore |
| Fossil(s): | Partial skull |
| Classification: | | Chordata | Reptilia | Crocodylomorpha | Goniopholididae | |
Calsoyasuchus (meaning "[Dr. Kyril] Calsoyas' crocodile") is a genus of goniopholidid mesoeucrocodylian that lived in the Early Jurassic. Its fossilized remains were found in the Sinemurian-Pliensbachian-age Kayenta Formation on Navajo Nation land in Coconino County, Arizona, United States. Formally described as C. valliceps, it is known from a single incomplete skull which is unusually derived for such an early crocodile relative. This genus was described in 2002 by Ronald Tykoski and colleagues; the species name means "valley head" and refers to a deep groove along the midline of the nasal bones and frontal bones.