Although he had a real son MIYOSHI no Masanaga, who had the ranks of Jugoinoge (Junior Fifth Rank, Lower Grade) Daigeki (Senior Secretary) and San Hakase, he made his disciple, MIYOSHI no Tameyasu, his heir by adopting him.
実子三善雅仲（従五位下大外記・算博士）がいたものの、算道に通じた門人三善為康を養子に迎えて跡継ぎとした。