The 2010–11 Magners League was the tenth Celtic League season and the fifth with Magners as title sponsor. The regular season began on 3 September 2010 and finished on the weekend of 6–8 May 2011. During these stages, each team played every other team both home and away and were awarded points according to the standard bonus point system. This was the second season to follow the play-off structure to determine the Magners League champion, with the top four teams qualifying for the semi-finals. The winner of each semi final advanced to the Grand Final, which took place 28 May and was hosted by the team that finished highest in the table following the regular season. The title was won by Munster who defeated Leinster by 19–9 at Thomond Park.

Munster Rugby is one of the professional provincial rugby teams from the island of Ireland. They compete in the United Rugby Championship and the European Rugby Champions Cup. The team represents the IRFU's Munster Branch, which is responsible for rugby union throughout the Irish province of Munster. The team motto is "To the brave and faithful, nothing is impossible." This is derived from the motto of the MacCarthy clan – "Forti et Fideli nihil difficile". Their main home ground is Thomond Park, Limerick, though some games are played at Musgrave Park, Cork.