The members of ACIDMAN founded the band when they were students at the same private high school in Saitama. The friends stuck together through university and held their first concerts in 1997 in Shimokitazawa. On these live outings they distributed their first three demo tapes to the audience for free.
Only two years later, the band had their first line-up change; the vocalist, Shiibashi Takeshi, left the band and the guitarist, Ooki Nobuo, took his place, thus, changing from the quartet that they were to the trio they are today. Ooki Nobuo graduated as a pharmacist/chemist not long after that and ACIDMAN really kicked off their career.
In 2001, they signed with the indie label Nomadic Records and their single, Sekitou, ranked third on the indie charts. In March 2002, they released the mini-album, Sankazora, which, unfortunately, was not very successful. They toured again and performed at smaller events next to bands like Husking Bee and Bloodthirsty Butchers.
Later that year the major label Toshiba/Emi offered them a contract. They released two singles on the new label, a new press of their first single and, in October, their very first album, Sou. This album ranked ninth on the Oricon charts and earned ACIDMAN the Japan Gold Disc Award for the best newcomer of the year 2003.
It took another year before they released their next album, Loop. A support musician worked with them on this release, but the trio remained the way they were and the support musician didn't become an official part of their line-up. A big tour followed the release of the album and they also performed at events with bands like THE BACK HORN, Faridas Café, The band Apart and Husking bee. After their touring period, the band headed in to the studio. This fruitful period yielded two new singles and the album, Equal, in September 2004.
In the following years they resumed their steady pace in releases, producing singles, albums and performing national tours. In 2011 they decided to play some acoustic lives with unplugged versions of their own songs, resulting in some releases in DVD and CD. At the end of that year they gave start to their anniversary celebration, commemorating the fifteen years since their formation and ten years since their major debut. ACIDMAN released two best-of albums and performed a special tour for the occasion. The celebration lasted until the end of 2012, year which they released their first instrumental album, This is instrumental. In 2013 the group brought out their ninth album titled Shin Sekai.
