Seiichi Okura graduated from Commercial Science Department of Waseda University (1931).
Seiichi Okura entered Unpan Goshi (Joint-Stock Transportation) Company (1932) and as it was merged into Nihon Transportation Company became member of the new company (1941). Appointed chief secretary of Chubu (Central Japan) District Headquarters of All-Japan Communications Workers' Union twice (1946 and 1951) and then became chairman of its Executive Committee (1952). Appointed vice-chairman of Council of All Japan Traffic & Communications Workers' Union (1951). Attended the 35th General Assembly of I.L.O. as representative adviser of labor (1952). Elected to House of Councilors (1953).
He became vice-president of Chubu District Cooperative Council of All-Japan Traffic & Transportation Workers' Union, member of Nagoya District Mediation Committee of National Railway and member of Labor Relations Board of Aichi Prefecture.