From the perspective of historical science, the study of the Republic of Vietnam regime contributes to a certain stage of development in modern Vietnam history. In particular, in-depth study of the diplomatic activities of the Republic of Vietnam regime (1955-1963) from a diplomatic perspective also brought new insights into the Republic of Vietnam regime. The Diplomatic Book of the Saigon Government (1955-1963) will focus on studying the diplomatic activities of the Republic of Vietnam regime during the period of President Ngo Dinh Diem's rule; restoring the entire diplomatic activities of the Republic of Vietnam government, paying attention to important bilateral relations that directly affect the formation and development of this regime in South Vietnam. The book's content helps fill in a vacant piece of modern Vietnamese history in general and modern Vietnamese diplomatic history in particular.