Part of the national parks system of Italy, the island was recently converted to a wildlife and marine preserve.

The surface is hilly,[1] covered by thick Mediterranean scrub and few trees, with the exception of a wooded area in the northern part of the island.

The west side of the island is more rocky and steep, while the east has wide, flat areas with a maximum height of 50 m (164 ft).

[2] As of 2008[update], 107.32 km2 (41 sq mi) of the surrounding marine and underwater environment is a protected natural area.

[1] From a geological point of view, the Asinara is part of the Nurra of north-western Sardinia, more than 80 percent made up by of metamorphic rock.

[1] Human habitation on the island dates back to the Neolithic Age, with Domus de Janas (sprites' houses) near Campu Perdu.

[1] About 100 families of Sardinian farmers and Genoese fishermen who lived on Asinara were obliged to move to Sardinia, where they founded the village of Stintino.

[9] There are many species of native and introduced mammals on the island, including horses, asses, goats, sheep, and pigs.

All of these have been turned over to the national park, and in tandem the marine protected area, who sorted out what will be kept and with what restoration is needed.

[1] There are strict regulations on the island put in place to guarantee the conservation of the marine and land habitats.

13.8.02, Presidential Decree 3.10.02), with numerous clauses, include no permission to use own vehicles, prohibition of sport fishing, anchorage and navigation with the exception of authorized means.

[1] The vegetation of Asinara is a typical Mediterranean macchia, with lentisk, Euphorbia, tree heath (Erica arborea), Calicotome spinosa, Phillyrea angustifolia, Phoenician juniper and cistus.

The marine setting is rocky in the eastern side, with steep slopes and ravines, but mainly sandy in the western area.

The shallowest part of the coast is colonized by two rare species, the red alga Lithophyllum lichenoides and the endangered giant limpet Patella ferruginea.