Sarcohyla crassa is a species of frog in the family Hylidae. It is endemic to the Sierra Madre de Oaxaca of Oaxaca, Mexico. It is also known as the aquatic treefrog, or when referring to the former Hyla bogertae, Bogert's aquatic treefrog.
Sarcohyla crassa occurs in streams in montane cloud forest at elevations of 1540m–2650mm (5,050feet–8,690feetm) above sea level. It is threatened by the loss of original montane forests and possibly chytridiomycosis.