According to the 2012 national census, the region had a population of 1,425,131, which was lower than the pre-census projection of 1,497,555.

[3]: page 2  For 2002–2012, the region's 3.2 percent average annual population growth rate was tied for the third highest in the country.

[3]: page 4  It was also the 22nd most densely populated region with 32 people per square kilometre.

The latter include the Assa, Gorowa, Kw'adza, Mbugwe, Datooga, Maasai and Barabaig and Irakw,[4] which is the largest ethnic group in the region.

One paved road passes through the western part of Manyara Region.