In June 2005, Kajiyama was selected Japan U-20 national team for 2005 World Youth Championship. At this tournament, he played 3 matches as defensive midfielder with Yuzo Kobayashi. In August 2008, he was selected Japan U-23 national team for 2008 Summer Olympics. At this tournament, he wore the number 10 shirt for Japan and played all 3 matches as defensive midfielder.