1984： Formed his own group Onuma Jazz Unit which played mainly modern jazz.
1986： Formed Fedayien with Daisuke Fuwa (bass) and Naohiro Kawashita (ts,vln).
1989： Joined Shibusa-shirazu Orchestra.
1996： Toured Germany with Fedayien and played at the Moels Jazz Festival.
1997： Toured Russia and Lithuania with Fedayien.
1998,2000： Toured Europe with Shibusa-shirazu and played at the Moers Jazz Festival.
2001： Formed Shiro Onuma Trio including Tetsu Watanabe (sax) and Hiroyuki Eizuka (bass).
2003： Formed M.A.S.H. with Junji Mori (sax) and Dairo Suga (piano).
2005： Toured Russia with Katsuyuki Itakura (piano).
2005： Formed Drums Duo with Heinz Geisser (drums).
2006: Toured Japan with Andreas Dormann (reeds).
Toured Japan with Bruce Eisenbeil (guitar).
2007: Formed Die Bande with Andreas Dormann (reeds) and Hiroyuki Eizuka (bass).