In June 1961, Miyamoto was selected the Japan national team for 1962 World Cup qualification. At this qualification, on June 11, he debuted against South Korea. He was selected Japan for 1964 Summer Olympics in Tokyo and 1968 Summer Olympics in Mexico City. He played all matches at both Olympics and Japan won the bronze medal 1968 Olympics. In 2018, 1968 Olympics team was selected Japan Football Hall of Fame. He also played at 1962, 1966 and 1970 Asian Games. At 1972 Summer Olympics qualification in 1971, Japan's failure to qualify for 1972 Summer Olympics. This qualification was his last game for Japan. He played 58 games and scored 19 goals for Japan until 1971.