Alaotra-Mangoro is a region in eastern Madagascar. It borders Sofia Region in north, Analanjirofo in northeast, Atsinanana in east, Vakinankaratra in southwest, Analamanga in west and Betsiboka in northwest. The capital of the region is Ambatondrazaka, and the population was 1,255,514 in 2018. The area of the region is 31,948 km² (12,335 sq mi).

Alaotra-Mangoro Region is divided into five districts, which are sub-divided into 82 communes.

The region is mainly populated by the Sihanaka in the north, and the Bezanozano in the south. Other minorities are present, notably the Merina.

With 120.000 ha of planted surface, the region constitutes the main rice basin of Madagascar. Other crops cover manioc (175.000 tonnes), potatoes (49.000 tonnes), corn (50.000 tonnes) and sugar cane (50.000 tonnes). Livestock (Zebu) reaches 265.000 heads and fishing 2000-2500 tons per year.

There is an important nickel mine near Moramanga/Ampitambe: the Ambatovy mine. Other mining activities are found in Andilamena, Ambatondrazaka and Didy where sapphire and ruby are mined.

17°49′48″S 48°25′48″E / 17.83000°S 48.43000°E / -17.83000; 48.43000