The potential move could be part of a drive to increase Glencore's clout as it seals its merger with fellow mining multinational Xstrata, the source said on Friday on condition of anonymity.
Both groups are headquartered in the tax-friendly Swiss canton of Zug.
Glencore is yet to comment on media reports that it is studying the South Africa listing.
The group was listed in London and Hong Kong in 2011, raising $7.5 billion in the process.
Its London listing was the third most lucrative market entry ever seen in Europe.
Glencore's merger with Xstrata is due to be completed by March 15, provided Chinese regulators give a green light.
The merger has already won the conditional approval of the European Commission as well as South African competition authorities.