The Super Eagles have fallen seven places to 59th place, in the November FIFA rankings released on Thursday.
Nigeria are no longer in the top 10 African nations in world football.
Ivory Coast (22) continue to lead the way in the continent and are followed by Algeria (26), Ghana (30), Cape Verde (32), Senegal (39), Tunisia (41), Cameroon (51), Congo (52), Guinea (53) and Congo DR (55).
Belgium are the highest-ranked team in the world.
The top five is completed by Germany, Argentina, Portugal and Chile.