Finance Minister Pravin Gordhan has attacked companies for smuggling money out of African countries, costing the continent billions, the SABC reported on Monday.
He told the annual G-20 African conference in Johannesburg that African economies would be better off if this type of looting did not take place.
"Think of how much African governments could do with this extra tax revenue," he said.
"Africa could be fundamentally in a better place with more schools, more infrastructure and more economic activity."
Gordhan also blasted big corporations which make huge profits, but contribute little to the tax base.
"Without the tax coming from corporates, governments are forced to raise the tax on individuals or cut spending."