The park occupies about 135,000 hectares and consists of patches of thick dry tropical forest interspersed with less dense areas.

There are also savannah, scrub and sandy eroded rock areas and some land is farmed by the indigenous Sakalava people.

[2] Ankarafantsika National Park is mostly woodland, and the tree species are typical of dry tropical forest.

Notable examples include the flowering bush mpanjakabenitany (Baudouinia fluggeiformis), the katrafay (Cedrelopsis grevei) used in traditional medicine, the small tree lohavato (Hymenodictyon occidental) and sakoanala (Poupartia silvatica), a large tree with conspicuous flowers.

The greater big-footed mouse (Macrotarsomys ingens) is a recently described small rodent known only in the park and its vicinity.