Kubo was born in Chikuzen, Fukuoka on June 18, 1976. After graduating from Chikuyo Gakuen High School, he joined J1 League club Sanfrecce Hiroshima in 1995. He debuted in 1996 and became a regular striker as Takuya Takagi successor from 1998. However the club was relegated to J2 League in 2002. He moved to Yokohama F. Marinos in 2003. In 2003, the club won the champions J1 League. He was also selected Best Eleven and "Japanese Footballer of the Year award". However his opportunity to play decreased for low back pain from 2004. He moved to Yokohama FC in 2007. However the club was relegated to J2 and he also did not play many matches. After that, he returned to Sanfrecce Hiroshima in 2008 and moved to Japan Football League club Zweigen Kanazawa in 2010. He retired end of 2011 season.