Birth Date：September 22nd 1982
Height：178cm
Weight：72kg
Specialty：Breaststroke
Birth Place：Tokyo
Affiliation：Coca-Cola Japan
Official website「FROG TOWN」：http://www.frogtown.jp/
Sponsors：Lotte Co., Ltd.(Xylitol)、MIZUNO、Coca Cola Japan Co., Ltd.、TBC GROUP Co., Ltd.

At the World Championships in July 2003, Kitajima won gold medals in both the 100m and 200m and hit the world records for the second time.

At the Athens Olympic Games in August 2004, Kitajima achieved his goals, in attaining Gold medals for both the 100m and 200m breaststroke. Also, as a member of the men’s 400m medley relay team, he got the Olympic bronze medal with a Japanese record. He continued to perform well in 2005 with a Japan record on 50m and 100m at the World Championship. In 2006, after qualifying for the World Championships at the Pan Pacific games, In 2006, Kitajima won the gold medal for 100m & 200m breaststroke at the Asian Games. At the 2007 Japan Open, Kitajima broke his own short course Japanese records.

He also won the gold medal in the 200m at the World Championships in March. Now, Kitajima is working hard on his training to aim for 2008 Olympics.