He joined Tsuyoshi Kohsaka’s A-Square MMA team in 2004 and began his career in 2005.

[3] Kikuno made his professional mixed martial arts debut in Japanese promotion DEEP's Future King Tournament 2005 defeating Hitoki Tsuti via doctor stoppage and Masashi Takeda via knockout.

At the 2009 DEEP Lightweight Tournament Kikuno became champion after defeating Koichiro Matsumoto via knockout.

Kikuno defeated Dida via a flurry of punches, winning his DREAM debut.

[8] He lost the fight via technical knockout in the first round and was subsequently released from the promotion.