In August 1979, when Koshida was a University of Tsukuba student, he was selected the Japan U-20 national team for 1979 World Youth Championship and played 3 matches. In December 1980, he was selected the Japan national team for 1982 World Cup qualification. At this qualification, on December 22, he debuted against Singapore. He played at 1982 Asian Games, 1984 Summer Olympics qualification and 1986 World Cup qualification. He played 19 games for Japan until 1985.