The department is surrounded by the French departments of Var, Alpes-de-Haute-Provence, the principality of Monaco, Italy on the east, and the Mediterranean on the south in the Provence Alpes Côte d'Azur Region.

Alpes-Maritimes includes the famous French Riviera coastline on the Mediterranean Sea with the important towns and cities of Cannes, Nice, Saint-Jean-Cap-Ferrat, and Antibes.

The area is mountaneous right down to the coast. This Southern area of the Alps is termed the Maritime Alps

The Maritime Alps are a mountain range in the south-western part of the Alps. They form the border between the French département Alpes-Maritimes and the Italian province of Cuneo. The Col de Tende separates them from the Ligurian Alps; the Maddalena Pass separates them from the Cottian Alps. The Mercantour National Park is part of the Maritime Alps.

The Maritime Alps are drained by the rivers Roya, Var and Verdon and their tributaries on the French side; by the Stura di Demonte and other tributaries of the Tanaro and Po on the Italian side.