According to the 2002 Tanzania National Census, the population of Nzega District was 417,097.

[1] According to the 2012 Tanzania National Census, the population of Nzega District was 502,252.

[2] According to the 2022 Tanzania National Census, the population of Nzega District was 574,498.

[3] Paved Trunk road T3 from Morogoro to the Rwanda border and T8 from Tabora to Mwanza pass through the district.

[4] The Tanzanian Central Line train - from Tabora to Mwanza - passes through the district from south to north.