Miyazaki has sung several songs in the Digimon series. He sang the evolution theme song for Digimon Adventure called "Brave Heart" and the two evolution theme songs for Digimon Adventure 02, called "Break Up" and "Beat Hit!", respectively. In addition, he sang the second evolution theme for Digimon Frontier, called "The Last Element". Moreover, he was featured in Yūki o Uketsugu Kodomotachi e(勇気を受け継ぐ子供達へ?, lit. "To the Children Who Inherit Courage"), along with all of the other singers of Digimon. He also sang the theme song for Mushrambo, called "Power Play".
His father is Naoshi Miyazaki （宮崎 尚志）and his elder brother is Michi Miyazaki （宮崎 道）, who are both composers. He was a guest at Expo Anime Brasil 2006 in São Paulo.