Karen Matheson OBE (born 11 February 1963) is a Scottish folk singer, who frequently sings in Scottish Gaelic. She is lead singer of the group Capercaillie and was a member of Dan Ar Braz's group L'Heritage des Celtes, with whom she often sang lead vocals, either alone or jointly with Elaine Morgan. She and Morgan received much acclaim for their joint lead vocal on the Breton language song "Diwanit Bugale", the French entry to the Eurovision Song Contest 1996. She made a cameo appearance in the 1995 movie Rob Roy singing the song "Ailein duinn".
She grew up in the small village of Taynuilt in the region of Argyll, western Scotland.
She was awarded an OBE in the 2006 New Year's honours list.
Matheson also appeared as a guest musician on Spirit of the West's 1997 album Weights and Measures.
Matheson performed a solo in Secret Garden's song "Prayer" in the 1999 album Dawn of a New Century.
She is married to fellow Capercaillie member Donald Shaw, and they have a son named Hector.