CocoRosie is an American musical group formed in 2003 by sisters Bianca "Coco" and Sierra "Rosie" Casady. The sisters were born and raised in the United States, but formed the band in Paris after meeting for the first time in years. Their music has been called "freak folk", and incorporates elements of pop, blues, opera, electronica, and hip hop.

CocoRosie began as a duo, with Sierra singing, playing the guitar, piano and harp, and Bianca singing and manipulating various children's toys, electronic and percussion instruments, as well as other exotic noisemakers. They subsequently added various backing musicians, usually a bassist, keyboardist, and beatboxer. They have been a very active touring group, playing across Europe, the United States, and elsewhere. They have released five full-length albums: La maison de mon rêve (2004), Noah's Ark (2005), The Adventures of Ghosthorse and Stillborn (2007), Grey Oceans (2010) and Tales of a GrassWidow (2013).