Karen Tweed is a London-born accordionist. Born in 1963, she works mainly on the piano accordion and has played with a number of bands, including Swåp, May Monday, The Poozies and the Kathryn Tickell Band.

She is also active as an arranger, composer and tutor. Her playing moves between fast melodic lines and more soulful accompaniment, and she is described as a leading exponent of the piano accordion.