Johannesburg birni ne, da ke a ƙasar Afirka ta Kudu. Ita ce babban birnin lardin Gauteng, da babban birnin tattalin arzikin ƙasar Afirka ta Kudu; babban biranen Afirka ta Kudu, 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.