With the announcement at the CAF congress in Cairo on Wednesday, Gabon replaces war-torn Libya, who withdrew last year as 2017 hosts because of the conflict raging in the country.
This is second time that oil-rich Gabon will stage the finals after co-hosting the 2012 edition with neighbours Equatorial Guinea.
As presented in their bid document, Gabon will use four venues for the 16-team tournament, set for January 2017.
They will be Libreville and Franceville, which were used in 2012, plus Port Gentil and Oyem where the stadiums will be ready in 14 months, Gabon Football Federation officials said.
Meanwhile, CAF has already designated the hosts of the 2019 (Cameroon), 2021 (Ivory Coast) and 2023 finals (Guinea)