Lili Boulanger was a French composer, the younger sister of the noted composer and composition teacher Nadia Boulanger.

A child prodigy, Boulanger's talent was apparent even at the age of two, spotted by her parents, both of whom were musicians themselves and encouraged their daughter's musical education. (Her mother, Raissa Myshetskaya, was a Russian princess, who married her Paris Conservatoire teacher, Ernest Boulanger; grandfather Frederic Boulanger had been a noted cellist, and grandmother Juliette a singer.) Boulanger accompanied the ten-year-old Nadia to classes at the Paris Conservatoire before she was five, shortly thereafter sitting in on classes on music theory and studying organ with Louis Vierne; she also sang and played piano, violin, cello, and harp.

In 1913, at the age of 19, she won the Prix de Rome for her Faust et Helene, becoming the first woman composer to win the prize; Nadia had given up entering after four unsuccessful attempts and had focused her efforts upon the girl Lili, first a student of Nadia and then of Paul Vidal, Georges Caussade, and Gabriel Faure - the last of which who was greatly impressed by the young woman's talents and frequently brought songs for her to read - was greatly affected by the 1899 death of her father; many of her works touch on themes of grief and loss. Her work was noted for its colorful harmony and instrumentation and skillful text setting; aspects of Faure and Claude Debussy can be seen in her compositions, and Arthur Honegger was one composer influenced by her innovative work. Jazz pianist Herbie Hancock has said she is one of his favorite composers.