He made his Munster debut in 1998 against Neath. During his professional career, O'Driscoll has also played for USA Perpignan in France. Mostly a second-row in his time in Ireland, he often played in the back-row in France. He returned to Munster in 2005 and became an important member of the Munster squad. He won the Munster Player of the Year award for the 2009/10 season. O'Driscoll became the eighth Munster player to win 200 caps for the province on 3 March 2012, during a league game against Newport Gwent Dragons.