This growth rate is one of the highest in the world and is a source of concern for the government and other international agencies. The population is predominantly young, with 49.2% under 15 years old and 2.7% over 65 years, and predominantly rural with only 21% living in urban areas.

A 2005 study stated that over 800,000 people (nearly 8 per cent of the population) in Niger are enslaved.

Niger has a wide variety of ethnic groups as in most West African countries. The ethnic makeup of Niger is as follows: Hausa (53.0%), Zarma-Sonrai (21.2%), Tuareg (10.4%), Fula (French: Peuls or Peulhs; Fula: Fulɓe) (9.9%), Kanuri Manga (4.4%), Tubu (0.4%), Arab (0.3%), Gourmantche (0.3%), other (0.2%). 

French, inherited from the colonial period, is the official language. It is spoken mainly as a second language by people who have received a formal western education and serves as the administrative language. Niger has eight main indigenous languages which are also classified as "national languages": Hausa (Hausa group), Zarma (Zarma-Sonrai group), Tamasheq (Tuareg group), Fulfulde (Fula group), Kanuri (Kanuri group), Tubu (Tubu group), Arabic (Arabic group) and Gourmanchéma (Gourmanché group).

 Each is spoken as a first language primarily by the ethnic group with which it is associated.Hausa and Zarma-Sonrai, the two most spoken languages, are widely spoken throughout the country as first or second languages.