Ryozo Makino graduated from German Law Course of Tokyo University (1911).
Ryozo Makino took a job in the Ministry of Postal Service. Left his job (1914) and served with Osaka Mercantile Marine (O.S.K. Line) Company. Left same (1915), and registered as a lawyer. Later served in the Ministry of Education and became Secretary to Minister. Elected to House of Representatives (1920), and re-elected nine times (up to 1955). He served as Parliamentary Councilor of Commerce and Industry, and Parliamentary.