Acting Secretary-General - Gladwyn Jebb (1900–1996) - 24 October 1945 – 1 February 1946
Secretary-Generals of the United Nations
- Trygve Lie (1896–1968) - 2 February 1946 – 10 November 1952
- Dag Hammarskjöld (1905–1961) - 10 April 1953 – 18 September 1961
- Thant (1909–1974) - 30 November 1961 – 31 December 1971
- Kurt Waldheim (1918–2007) - 1 January 1972 – 31 December 1981
- Javier Pérez de Cuéllar (1920–2020) - 1 January 1982 – 31 December 1991
- Boutros Boutros-Ghali (1922–2016) - 1 January 1992 – 31 December 1996
- Kofi Annan (1938–2018) - 1 January 1997 – 31 December 2006
- Ban Ki-moon (born 1944) - 1 January 2007 – 31 December 2016
- António Guterres (born 1949) - 1 January 2017 –