Otto made his debut with the Brussels Philharmonic in 1999, with Richard Strauss's Ein Heldenleben. With this orchestra he has performed the world premières of violin concertos by Jeroen D'hoe and Michel Tabachnik, both dedicated to Otto Derolez. His performance of John Williams' Violin Concerto has been highly acclaimed, as well as the Alban Berg Violin Concerto which he performed with Brussels Philharmonic under the baton of Carlos Kalmar.

Otto Derolez studied at the Royal Conservatories of Ghent and Brussels, with professors such as Rudolf Werthen, Keti Sbestyen and Philippe Hirschhorn. He graduated from the Internationale Musikakademie für Solisten (IMAS) in Wolfenbüttel (Germany) under the guidance of André Gertler. He also received support and guidance from Yfrah Neaman.

As a soloist, he has performed in prestigious concert halls all over the world, including the Amsterdam Concertgebouw, Birmingham Symphony Hall, Tokyo Opera City Concert Hall, Festival Hall in Osaka, Cité de la Musique in Paris, just to name a few.

An active chamber musician, he has been a member of the Prometheus Ensemble since 1992. With this ensemble he recorded Schubert's Octet and Trout Quintet, Stravinsky's l'Histoire du Soldat, Schoenberg's First Chamber Symphony and Transfigured Night. He has been a jury member of the International Verbier Festival Orchestra, as well as the International Violin Competition Henri Vieuxtemps.

As well as being concertmaster of Brussels Philharmonic, Otto is also Faculty Professor of YOA-Orchestra of the Americas. Composed of gifted young musicians from more than 25 countries, YOA bring together young talents with professionals from the most prestigious orchestras accross the world. The first Festival Internacional de Cuerdas Maestro Otto Derolez took place in Chile. In collaboration with the YOA Global Leadership Programme (GLP) and the Corporación de Adelanto Amigos de Panguipulli, 20 young talented violinists were offered the opporunity to work and study with Otto, over the course of one intensive musical week.