Frank O’Sullivan is a professional guitarist, composer, and educator based in Montreal.

After graduating from the Berklee College of Music in 2012, Frank quickly became an in-demand musician in the Montreal's Pop, R&B, Jazz, and Hip-Hop scenes. Maintaining a prolific and diverse career as an instrumentalist, he's performed and recorded with many artists like Malika Tirolien, Dominique Fils-Aimé, Salin, and Busty & The Bass, touring extensively around the world and appearing at renowned festivals and venues. In 2022, he was nominated for a Juno Award in the category of Best Contemporary R&B Recording for his co-production of the song Gifted by Kallitechnis.

Since 2020, Frank has released four full-length albums of original music, and in June 2024 he opened for Al Di Meola at the Montreal International Jazz Festival. Shortly afterwards, he performed at the Rimouski Jazz Festival, where he was awarded the Grand Prix de la Relève, which granted him a province-wide tour of Quebec in the summer of 2025.