Kubo was born in Yamaguchi on December 24, 1993. He joined J2 League club Kyoto Sanga FC from their youth team in 2011. Kyoto won the 2nd place in the 2011 Emperor's Cup. In June 2013, he moved to Swiss Super League club Young Boys. He played for the club 104 matches and scored 26 goals. In January 2017, he moved to Belgian First Division A club Gent. He played many matches in 2 seasons. In August 2018, he moved to German Bundesliga club Nürnberg on loan. However Nurnberg was relegated to 2. Bundesliga end of the 2018/19 season. In June 2019, he returned to Gent. In January 2020, he moved to Major League Soccer club FC Cincinnati.