[3] Inoue made his amateur mixed martial arts debut on February 9, 2014, when he faced Gaku Sakamoto at Deep - Nagoya Impact 2014.
Following this, Inoue compiled a professional record of 10–0, with wins over Yuya Shibata and Tomohiro Adaniya, before signing with the UFC in the winter of 2017.
Inoue made his promotional debut on June 17, 2017, at UFC Fight Night: Holm vs. Correia against Carls John de Tomas.
[6] Inoue was expected to face Jenel Lausa on September 23, 2017, at UFC Fight Night 117,[7][8] but was pulled from the card due to a dislocated shoulder.
[11] After departing from the UFC, Inoue faced Sean Santella in a flyweight bout at CFFC 72 on February 16, 2019.
[15] On January 24, 2020, news surfaced that Inoue was scheduled to face Trent Girdham at Rizin 21 – Hamamatsu on February 22, 2020.
[17] In his sophomore bout in the promotion, Inoue faced Shooto Watanabe at Rizin 22 – Starting Over on August 9, 2020.
[21] Inoue faced Shintaro Ishiwatari in the opening round of the Bantamweight Grand Prix at Rizin 28 on June 13, 2021.