Lead vocalist TAKA is a former member of the Johnny's Jimusho idol group NEWS. Members Toru and Ryota are former members of the rapping break dancing group HEADS. They released two indies mini-albums and made their major debut with their single, Naihi Shinsho in April of 2007.A nationwide tour predated the release of the band's debut studio album, Zeitakubyou, which was followed by two LPs, Beam of Light and Kanjou Effect, in 2008.
After Alex left the band in May 2009, the band released the single "Kanzen Kankaku Dreamer" on February 3, 2010. It was featured 9th in the Weekly Oricon Charts. They released their fourth studio album titled Niche Syndrome on June 9, 2010.
The band started when Toru, Alex and Ryota started it in high school. Shortly after the creation of the band Taka joined the group as the main vocals.
The group came up with the name "ONE OK ROCK" because they would book studio time at One o'clock. The Japanese pronunciation of ONE OK ROCK (ワンオクロック)is wanokurokku which sounds like One o’clock.
* Taka (森 内 寛 贵 Moriuchi Takahiro born April 17, 1988 in Tokyo) - Main Vocalist and guitarist and former NEWS member
* Toru (Yamashita 山下 亨 Tōru born December 7, 1988 Osaka) - Leader, Main Guitarist and vocalist and former member of the hip-hop dance group HEADS
* Ryota (小 浜 良 太 Kohama Ryota born September 4, 1989 in Osaka) - Bassist and former member of hip-hop dance group HEADS
* Tomoya (吉 智 也 Kanki Tomoya born 27 June 1987 in Hyogo ) - Drummer
* Alex (鬼澤 アレクサンタ ゙ Onizawa Alexander born 19 March 1988 in San Francisco) - Guitar Officially left the band in May 2009