Koji Takeuchi has eight losses against eight opponents on his MMA record. For a list of Takeuchi's best fights, refer to "Best fights of Koji Takeuchi".
On July 30, 2005 Koji Takeuchi faced off against Kabuto Kokage at age 31. He was coming in with a record of 3-8-5 (2). Takeuchi lost the fight via 2-round unanimous decision.
On September 26, 2004 Koji Takeuchi faced off against Komei Okada at age 30. He was coming in with a record of 3-7-5 (2). Takeuchi lost the fight via 2-round unanimous decision.
On October 31, 2003 Koji Takeuchi faced off against Ganjo Tentsuku at age 29. He was coming in with a record of 2-6-5 (1). Takeuchi lost the fight via 2-round unanimous decision.
On November 25, 2001 Koji Takeuchi faced off against Masato Fujiwara at age 27. He was coming in with a record of 2-5-4 (1), and Fujiwara was 25 years old and with a record of 2-5-4 (2). Takeuchi lost the fight via 2-round unanimous decision.
On September 27, 2001 Koji Takeuchi faced off against Hiroshi Tsuruya at age 27. He was coming in with a record of 2-4-4 (1), and Tsuruya was 30 years old and with a record of 4-1-3 (3). Takeuchi lost the fight via 2-round unanimous decision.
On June 30, 2001 Koji Takeuchi faced off against Takeshi Yamazaki at age 27. He was coming in with a record of 2-3-4 (1). Takeuchi lost the fight via 2-round majority decision.
On March 28, 1999 Koji Takeuchi faced off against Kazuya Abe at age 24. He was coming in with a record of 0-2 (0). Takeuchi lost the fight via 2-round unanimous decision.
On January 27, 1999 Koji Takeuchi faced off against Kohei Yasumi at age 24. He was coming in with a record of 0-1 (0), and Yasumi was 20 years old and with a record of . Takeuchi lost the fight via 2-round unanimous decision.
