The 2005–06 season was the 103rd in the history of the Southern League, which is an English football competition featuring semi-professional and amateur clubs from the South West, South Central and Midlands of England and South Wales. At the end of the season Eastern and Western divisions were restructured after a single Division One of the Isthmian League was divided into Division One North and Division One South, while large number of the clubs left to the Isthmian League. For the next season regional divisions were renamed Division One Midlands and Division One South & West.