Lili Haydn (born 1969) is a Canadian-born rock violinist, vocalist, recording artist, and composer. As a child, she pursued a career as an actress; at age eight she discovered the violin and began to focus on classical music. By the time Haydn was fifteen, she had played with the Los Angeles Philharmonic.

After graduating from Brown University with a B.A. in political science, Haydn started composing original songs and became one of the most requested session violinists around Los Angeles. By the time she signed with Atlantic in 1997, she had embraced a variety of genres, having played with Quwaali musician Nusrat Fateh Ali Khan, Porno for Pyros, Tracy Chapman, The Jayhawks, Brandy, Tony! Toni! Tone!, No Doubt, Tom Petty and more. In addition, she has played with, sung with, and opened for Sting, Josh Groban, Herbie Hancock, Robert Plant & Jimmy Page, Matchbox 20, Seal, and George Clinton, who calls her "the Jimi Hendrix of the violin".