The Academy Award for Best Original Score is an award presented annually by the Academy of Motion Picture Arts and Sciences (AMPAS) to the best substantial body of music in the form of dramatic underscoring written specifically for the film by the submitting composer. Some pre-existing music is allowed, though, but a contending film must include a minimum of original music. This minimum since 2021 is established as 35% of the music, which is raised to 80% for sequels and franchise films. Fifteen scores are shortlisted before nominations are announced.

The 11th Academy Awards were held on February 23, 1939, at the Biltmore Hotel in Los Angeles, California, and hosted by Frank Capra.