Takeo Ozawa studied at Tokyo University of Commerce (now named Hitotsubashi University).
He entered Ministry of Foreign Affairs (1936), appointed a diplomatic student secretary in America. Served as assistant to the consul at Shanghai (1938), and then served in several offices of the ministry in Japan. Appointed first secretary of the Japanese diplomatic office at Peru (1952), and chief of the First Section of the Asia Bureau of the ministry. Assigned to the Provisional Reparations Office of the ministry (1955).