AAA (pronounced as Triple A (トリプル・エー)), standing for the English acronym Attack All Around, debuted in 2005 with the single BLOOD on FIRE as an eight-piece co-ed group, but had originally been planned to be a six-member group.

At the time of formation and debut, the group consisted of Takahiro Nishijima (西島隆弘), Naoya Urata (浦田直也), Shuta Sueyoshi (末吉秀太), Shinjiro Atae (與真司郎), Mitsuhiro Hidaka (日高 光啓), and Misako Uno (宇野 実彩子) as the only female member. However, their company, Avex, later decided to add two more female members, which include Yukari Goto (西島 隆弘) and Chiaki Ito (伊藤千晃). All eight had experience in the entertainment agency and had auditioned for the group and trained under the label’s trainee program called Avex Artist Academy.

Unfortunately, member Yukari Goto (西島 隆弘) would leave the group. The official statement regarding her departure was cited as health reasons. Goto, however, would not be the last member to leave the group. Despite the group’s ever-growing popularity, the group would go through several other member departures and additions. These would include Ito Chiaki (伊藤千晃) and Urata Naoya (浦田直也).

Throughout the years, each member would start their own solo careers, which include music and acting among other things. Some of the members go by a different stage name.

The group currently consists of five members, (four boys and one girl) which include Takahiro Nakajima (西島 隆弘), Misako Uno (宇野 実彩子), Mitsuhiro Hidaka (日高 光啓), Shinjiro Atae (與 真司郎), and Shuta Sueyoshi (末吉 秀太). On January 15, 2020, it was announced that the group would temporarily disband and cease activities for the time being, but the members would continue their solo activities.