The agreement was signed at a summit in the Rwandan capital, Kigali.
It is hoped that the deal will come into force within six months and increase prosperity for one point two billion Africans.
The agreement will need to be ratified by the parliaments of all signatories before it becomes a reality.
The African Continental Free Trade Area will remove barriers to trade, like tariffs and import quotas, allowing free flow of goods and services between its members.
Ten countries, including Nigeria, have refused to sign the deal. APP/AFP