Boudewijn Jansen studied piano and orchestra conducting at the Utrechts Conservatorium, besides cello and singing. He gained his first major experience at the opera studio of the Nationale Reisopera. He was also the musical director of Stichting Kameropera Nederland. Since 1994, Boudewijn Jansen has been a rehearsal director and assistant conductor with Dutch National Opera, where he made his debut as a conductor in 2001 with the Netherlands Radio Philharmonic Orchestra in Jenůfa, and later conducted the Netherlands Philharmonic Orchestra in Die Meistersinger von Nürnberg. He has also directed many rehearsals of the Dutch National Opera Chorus. In 2013, he conducted the Netherlands Wind Ensemble and the Chorus at the coronation of King Willem-Alexander.
Boudewijn Jansen has conducted leading choirs in the Netherlands, including Toonkunstkoor Amsterdam, of which he has been artistic director and conductor since 2003, VU-Kamerkoor, which he joined in 1991, and the Netherlands Concert Choir. He has also conducted the Netherlands Philharmonic Orchestra, the Netherlands Chamber Orchestra, the Netherlands Radio Philharmonic Orchestra, the Rotterdam Philharmonic Orchestra, the North Netherlands Symphony Orchestra, Combattimento Consort and the Netherlands Wind Ensemble. His collaborations with great conductors like Sir Simon Rattle, Pierre Boulez and Mariss Jansons have been of great musical importance to him.