Greenhall's dog-faced bat (Cynomops greenhalli) is a South American bat species of the family Molossidae. It lives in Colombia, Peru, Ecuador, Venezuela, the Guianas, northeastern Brazil and Trinidad.
This insect-eating bat measures 40–97 mm in length. It has yellowish-brown to black coloration on its upper body and a grey underside, with a broad face and widely separated eyes. Its ears are short and rounded, the antitragus square, its lips unwrinkled and the snout broad.
The dog-faced bat lives at low elevations. Colonies of 50–77 roost in hollow branches of large trees. Males and females stay together throughout the year. It is named after Arthur Greenhall, a scientist who led the rabies program at the Trinidad Regional Virus Laboratory in Port of Spain, Trinidad.