This article is about the demographic features of the population of Tanzania, including population density, ethnicity, education level, health of the populace, economic status, religious affiliations, and other aspects of the population.

The population distribution in Tanzania is extremely uneven. The population density varies from 1 person per square kilometre (3 per sq. mi.) in arid regions to 51 per square kilometre (133 per sq. mi.) in the mainland's well-watered highlands to 134 per square kilometre (347 per sq. mi.) in Zanzibar. More than 80 percent of the population is rural. Dar es Salaam is the de facto capital and largest city. Dodoma, located in the centre of Tanzania, is the de jure capital, although action to move government buildings to Dodoma has stalled.

The African population consists of more than 120 ethnic groups, of which the Sukuma, Haya, Nyakyusa, Nyamwezi, and Chagga have more than 1 million members.^{[citation needed]} The majority of Tanzanians, including such communities as the Hehe, Sukuma, and the Nyamwezi, are Bantu speaking groups. Groups of Nilotic or related origin include the nomadic Maasai and the Luo, both of which are found in greater numbers in neighbouring Kenya. Two small groups speak languages of the Khoisan family peculiar to the Bushman and Khoikhoi peoples. Cushitic-speaking peoples, originally from the Ethiopian highlands, reside in a few areas of Tanzania. Other Bantu speaking were refugees from Mozambique.