Fifa rates Sierra Leone above Nigeria
South Africa were the biggest African risers in the Fifa rankings this month, edging up four places to 67th spot.
Elsewhere, Sierra Leone rose two places to 61st spot, to lie above Nigeria (63) for the first time in their history.
"We are ranked now among elite nations and that is very good news for the country's government, youth and football administrators," said Sierra Leone FA official Abdul Rahman Swarray.
Ivory Coast remain top in Africa at 15th, with Ghana second highest (22nd).
DR Congo were the biggest fallers, dropping five places to 124th position.
The 1974 African champions are now rated below the likes of Benin, Central African Republic and Sao Tome e Principe.
Similarly, Nigeria - who have competed at four World Cups and won two Africa Cup of Nations tournaments - have now dropped below Sierra Leone in the rankings.
Sierra Leone, whose population of six million is dwarfed by Nigeria's total in excess of 160m, have never travelled to a World Cup and have only ever competed at two Nations Cups - in 1994 and 1996.
Swarray, who works for the Sierra Leone FA (SLFA) as Acting General Secretary, believes the Leone Stars' place above Nigeria is a sign that the country's administrative efforts are on track.
"I want to congratulate Sierra Leoneans, the SLFA and all stakeholders as we are moving together as a nation in the development of the game," he told BBC Sport.
"It is no surprise that we are ranked above Nigeria because we are doing a lot of things in terms of development, and we are moving gradually in terms of international success when it comes to the national teams.
"We are putting a lot of structures in place when it comes to the administrative aspect of the game - and we are also putting a lot of effort into the technical aspect.
"We have a technical director, who is currently embarking on the development of grassroots and youth football, as well as in the development and education of the coaches - so it's no surprise we're moving ahead of countries with a huge population like Nigeria."
Swarray also praised the work of Swedish Lars Olof Mattson, who was appointed national coach in January 2011.
The top seven in the African rankings were unchanged, with Tunisia moving up to eight as Egypt dropped down the rankings.
World and European champions Spain still top the rankings.