Mikael Oskarsson was born in Eskilstuna 1966 and started his musical career playing trumpet at the age of 9. Later on, he started playing trombone at the age of 15. Mikael Oskarsson was a student at the Stockholm Royal College of Music between 1987 and 1991, where his teachers were Sven-Erik Eriksson, Jan Andersson and Michael Lind. In 1992 Mikael Oskarsson went to Chicago to study with Michael Mulcahy, Charlie Vernon and Arnold Jacobs, all members of the Chicago Symphony Orchestra.
In the 1990s he was employed at the Stockholm Wind Ensemble as an euphonist/trombonist before being appointed principal trombone with the Swedish Radio Symphony Orchestra in 1999. Mikael Oskarsson is also well known as chamber musician, soloist and pedagogue. He has performed as soloist with the Swedish Radio Symphony Orchestra, the Stockholm Wind Ensemble, The Gothenburg Wind Ensemble, and the Swedish Army Band, among others. He works regularly with the Stockholm Chamber Brass, Chamber Orchestra of Europe and Stockholm X-brass, to name a few. Mikael Oskarsson also teaches trombone at Lilla Akademien in Stockholm.