[1] He held the positions of the chairman of the board of directors of Toray Industries, vice-president of Mitsui Bank, president of Mitsui Petrochemicals Industries, vice-chairman of Nihon Keidanren (Japan Business Federation), chairman of Japan Chemical Fibers Association and others.

He dedicated himself to reconstructing Japanese National Railways as the 4th chairman of audit committee thereof.

[3][4] His older sister, Kinu, married into a distinguished family in Akasaka-juku (Nakasendō), the Yabashis that Emperor Shōwa officially visited in 1946.

During this period, he successively held the positions of vice-chairman of Nihon Keidanren (Japan Business Federation), chairman of Japan Chemical Fibers Association, general manager of Tokyo Metropolis of Ise Shrine Revered Board, member of the board of Japan Association of Corporate Executives, member of Tax Research Committee of Prime Minister's Office (Japan), member of National Language Council of Ministry of Education, Science and Culture and so on.

The chairman of the funeral ceremony of Kizo Yasui was Fumio Takagi[12]（jp）, former Vice Minister of Ministry of Finance and former president of Japanese National Railways.