He graduated from the Law Department of Tokyo University (1930) and became a diplomatic student secretary of Ministry of Foreign Affairs, assigned in Britain.
Later served in several sections of the ministry in Japan, appointed secretary to the Minister of Foreign Affairs (1941).
Hisanaga Shimazu appointed Consul General at Rangoon (1943), vice-director of the Repatriation Board (1948), director of the Political Affairs Bureau of the ministry (1949), director of the Secretariat of the Minister of Foreign Affairs (1951) and then director of the Overseas Office at New York (1952).
Then, appointed Consul General at New York, councilor to the Japanese Embassy in Washington (1954). Assigned to the Deliberation Office of the ministry (1954) and appointed director of the Secretariat of Foreign Minister (1955).