Daisuke Ono is a prominent Japanese voice actor and singer born on May 4, 1978, in Sakawa, Kōchi Prefecture. He graduated from Nihon University's College of Art, where he initially studied television program production. A pivotal experience during the creation of a radio drama, where he stepped in as a performer due to a staff shortage, steered him toward a career in voice acting. He later trained at the Aoni Coaching School Sunday Class before beginning his professional career in 2001, initially affiliated with the talent agency Mausu Promotion. Since February 2016, he has worked as a freelance voice actor.

Ono's early career consisted of numerous minor roles, but his first leading role came in 2005 as Yukito Kunisaki in the television anime Air. His performance as Itsuki Koizumi in the 2006 hit series The Melancholy of Haruhi Suzumiya significantly raised his public profile and is considered a turning point in his career. This success led to a succession of major character roles, establishing him as a leading figure in the industry. He is widely recognized for voicing Sebastian Michaelis in Black Butler, a role that earned him his first Seiyu Award for Best Lead Actor. Another landmark role is Jōtarō Kūjō in the JoJo's Bizarre Adventure anime series, a character he has voiced across multiple adaptations and video games, beginning with JoJo's Bizarre Adventure: All Star Battle. Ono has cited JoJo's Bizarre Adventure as a personal favorite manga that influenced his decision to enter the entertainment world.

His extensive filmography demonstrates a remarkable range, from cool and collected characters to comedic and eccentric ones. Among his most iconic and well-known roles are the determined Erwin Smith in Attack on Titan, the volatile Shizuo Heiwajima in Durarara!!, the eccentric Jyushimatsu in Osomatsu-san, the precise Shintarō Midorima in Kuroko's Basketball, and the intense Riki Nendō in The Disastrous Life of Saiki K.. He has also lent his voice to a wide array of other characters, including Killer T Cell in Cells at Work!, Drole in The Seven Deadly Sins, Sion Astarl in The Legend of the Legendary Heroes, Yakumo Saitō in Psychic Detective Yakumo, and Kyōsuke Hori in Horimiya. His work extends to video games, where he is known for roles such as Silver the Hedgehog in the Sonic the Hedgehog series, Frederick in Fire Emblem: Awakening, Nobuyuki Sanada in the Samurai Warriors series, and Jing Yuan in Honkai: Star Rail.

In addition to his solo work, Ono is known for his frequent collaborations and partnerships. Since 2007, he has co-hosted the popular radio program Dear Girl: Stories with fellow voice actor Hiroshi Kamiya, a partnership for which they have won awards and formed the musical unit Masochistic Ono Band. He is also the leader of DABA, a project group of male voice actors all born in 1978, and has been the host and leader of the annual live event Original Entertainment Paradise (OrePara) since 2008.

As a singer, Ono began his music career in 2007 with the mini-album Hinemosu and has since released multiple singles and albums under the Lantis label. His musical work includes both original material and character songs related to his anime roles.

Ono's talent and contributions to the voice acting industry have been recognized with numerous prestigious awards. He won the Seiyu Award for Best Supporting Actor in 2008. He has won the Seiyu Award for Best Lead Actor twice, first in 2010 for his role as Sebastian Michaelis in Black Butler, and again in 2015 for his performances as Jōtarō Kūjō in JoJo's Bizarre Adventure, Seishū Handa in Barakamon, and others. In that same year, 2015, he also received the Seiyu Award for Best Personalities for his work on the Dear Girl: Stories radio show, as well as the Voice Actor Award at the Tokyo Anime Award Festival.