In 2003, Kawasahima was selected the Japan U-20 national team for 2003 World Youth Championship and played all 5 matches. In February 2008, he was selected the Japan national team for 2008 East Asian Football Championship. At this tournament, he debuted against North Korea on February 17. However he could not play many matches behind Seigo Narazaki. In 2010, he was selected the Japan for 2010 World Cup. In May, he became a first choice goalkeeper instead Narazaki just before the 2010 World Cup. Kawashima played all 4 matches at the 2010 World Cup and Japan qualified to the knockout stage. After the 2010 World Cup, Narazaki retired from national team and Kawashima became a egular goalkeeper under new manager Alberto Zaccheroni. In 2011, he played at 2011 Asian Cup and won the champions. He also played at 2013 Confederations Cup, 2014 World Cup and 2015 Asian Cup. Although he lost his position behind Shusaku Nishikawa from 2015, Kawashima played many matches again from 2017. In 2018, he was selected the Japan for 2018 World Cup. He played all 4 matches and Japan qualified to the knockout stage. He also played at 2019 Copa América. He played 91 games for Japan until 2019.