Ōno studied at the Tokyo National University of Fine Arts and Music, and with Wolfgang Sawallisch and Giuseppe Patanè at the Bavarian State Opera, as a scholar of the Japanese Ministry of Culture.

In August 2002, he became music director of La Monnaie (Brussels), after his debut there in March 2001, conducting Salvatore Sciarrino's chamber opera Luci mie traditrici.

Other contemporary operas that Ōno conducted with La Monnaie included Philippe Boesmans' Julie[5] and Wintermärchen,[6] and the world premiere of Toshio Hosokawa's Hanjo at the Aix-en-Provence Festival (2004).

[9] In January 2014, the Barcelona Symphony and Catalonia National Orchestra (OBC) announced the appointment of Ōno as its next music director, effective September 2015, with an initial contract of 3 years,[10] which has since been extended until the end of the 2021–2022 season.

[15] Other new works Ōno has commissioned include Mark-Anthony Turnage's Hibiki, which premiered at Suntory Hall in November 2016[16] before featuring at the 2017 BBC Proms[17] and which won the 2018 Royal Philharmonic Society award for Large-Scale Composition.