In 2015, Kitajim won the Sydney Marathon with a time of 2:12:44.[2] He also won the Nobeoka West Japan Marathon.[1]
2016 season
Kitajima finished 2nd at the 2016 Lake Biwa Marathon and was the top finishing runner from Japan. As this was a qualifying race for the Japanese Olympic Team he earned selection for the 2016 Olympics,[3] He earned second place by passing Suehiro Ishikawa with one kilometer to go.[1] where he finished 93rd overall.