Diane Vallesteros is a Canadian film and media composer based in Toronto, Canada. Recognizing her passion for and the importance of storytelling through music in media, she creates emotionally resonant melodies within her work. She has composed for award-winning films such as, Ahon and Me+Her. Her most recent film collaborations explore the emotional core of real-life stories and human experiences, such as: Deux moments de vie, Sorry, It's A Girl, Outsiderness, and How She Dares. Her music contributions can also be heard in feature films, Lady Parts, and Call Me Crazy (Amazon Prime US, Tubi).

In 2022, Diane was a selected participant of SOCAN Foundation’s Screen Music Lab. In the same year, she received the Honourable Prize award for her work, The Blue Umbrella, under the Animated category in SOCAN Foundation’s Emerging Screen Composer Awards. Most recently, she became part of the 2025-2026 participating cohort of the Women In Post program held by The Academy of Canadian Cinema & Television, sponsored by Netflix.