The reserve is located in the Gulf of Guinea off the west coast of Africa, and is managed by the regional government of Príncipe.

The surface area of the reserve is 71,592.5 hectares (276.420 sq mi), subdivided as follows: The island is characterized by its gentle relief in the northern half of the island and a mountain range in the southern half composed of several phonolitic peaks with altitudes between 500 and 948 meters (1,640 and 3,110 ft) where there is a patch of primary rainforest.

The difference in geomorphology and terrain between the two sides, results in differentiated bioclimatology, has influence in the distribution of major types of ecosystems of the island, such as lotic (river) systems in the area of the massif and its valleys and lentic (lake) systems in the northern plains area.

[1] The biosphere reserve is home to great biodiversity in terrestrial as well as in marine ecosystems, with high rates of endemism in many groups of organisms, especially vascular plants, molluscs, insects, birds, reptiles and bats.

[1] As of September 2012[update], the resident population in the reserve was 6.737 inhabitants, all of whom live in the transition zone as all the islets are uninhabited.