The Hispaniolan giant tree frog (Osteopilus vastus), or Hispaniola tree frog, is a species of frog in the family Hylidae endemic to Hispaniola, found in both the Dominican Republic and Haiti.

[2] Populations from the southern part of Hispaniola may represent a separate, as yet undescribed species.

They are primarily found in mesic broadleaf forests but also in a range of agricultural habitats, such as cacao and coffee plantations and pastures.

They are often found along creeks and streams; males call from trees overhanging running water.

[1] The species is threatened by habitat loss caused by degradation of streams and deforestation.