Unquillosaurus, signifying "Unquillo river lizard," is a genus of theropod dinosaur, potentially belonging to the maniraptoran or carnosaurian group. This dinosaur lived during the Late Cretaceous period in the Los Blanquitos Formation of Salta Province, Argentina. The genus is represented by a sole species, U. ceibalii, which is known solely from the remains of a fossilized pubis, a bone from the pelvis. The limited fossil evidence suggests that Unquillosaurus likely measured around 2 to 3 meters (6.6 to 9.8 feet) in total body length.