Miyamoto was born in Tondabayashi on February 7, 1977. He joined J1 League club Gamba Osaka from their youth team in 1995. He became a regular player as center back from later 1990s. He also served as a captain. He played 295 matches for the club in 12 seasons. In 2005, the club won the champions J1 League. In 2007, he moved to Austrian Bundesliga club Red Bull Salzburg. In January 2009, he returned to Japan and signed with Vissel Kobe. He retired end of the 2011 season.