Johannesburg birni ne, da ke ƙasar Afirka ta Kudu. Birnin ne babban birnin lardin Gauteng, kuma babban birnin tattalin arzikin ƙasar Afirka ta Kudu; manya biranen Afirka ta Kudu su ne, Pretoria, Cape Town da Bloemfontein ne. Johannesburg tana da yawan jama'a 8,434,292, bisa ga ƙidayar 2011. An gina birnin Johannesburg a shekara ta 1886.