The leaders of the League of Nations consisted of a Secretary-General, Deputy Secretary-General and a President of the Assembly selected from member states.
| Portrait | Name | Term | Country | ||
|---|---|---|---|---|---|
| 1 | Jean Monnet | 1919–1923 | |||
| 2 | Joseph Avenol | 1923–1932 | |||
| 3 | Pablo de Azcárate | 1933–1936 | |||
| Massimo Pilotti | |||||
| 4 | Seán Lester | 1937–1940 | |||
| 5 | Francis Paul Walters | 1940-1946 |
| Nation | Name | Term | |
|---|---|---|---|
 United States | Raymond B. Fosdick | 1919 (provisional) | |
| Bernardo Attolico | 1919–1920 | ||
 Japan | Nitobe Inazo | 1919–1926 | |
| Dionisio Anzilotti | 1920–1921 | ||
 Germany | Albert Dufour-Feronce | 1927–1932 | |
| Giacomo Paulucci di Calboli | 1927–1932 | ||
| 1927–1933 | |||
| Germany | 1932–1933 | ||
| Francis Paul Walters | 1933–1939 | ||
| Vladimir Sokoline | 1937–1939 | ||
 Argentina | 1938–1943 | ||
 Greece | Thanassis Aghnides | 1939–1942 |
| Nation | Portrait | Name | Term |
|---|---|---|---|
| Léon Bourgeois | 1920 | ||
| Paul Hymans | 1920–1921 | ||
| Herman Adriaan van Karnebeek | 1921–1922 | ||
| Agustín Edwards | 1922–1923 | ||
| Cosme de la Torriente y Peraza | 1923–1924 | ||
| Giuseppe Motta | 1924–1925 | ||
| Raoul Dandurand | 1925–1926 | ||
| Afonso Costa | 1926 | ||
| Momčilo Ninčić | 1926–1927 | ||
| Alberto Guani | 1927–1928 | ||
| Herluf Zahle | 1928–1929 | ||
| José Gustavo Guerrero | 1929–1930 | ||
| Nicolae Titulescu | 1930–1932 | ||
| Paul Hymans | 1932–1933 | ||
| Charles Theodore Te Water | 1933–1934 | ||
| Rickard Sandler | 1934 | ||
| Francisco Castillo Nájera | 1934–1935 | ||
| Edvard Beneš | 1935–1936 | ||
| Carlos Saavedra Lamas | 1936–1937 | ||
| Tevfik Rüştü Aras | 1937–1937 | ||
| Sir Sultan Muhammed Shah, Aga Khan III | 1937–1938 | ||
| Éamon de Valera | 1938–1939 | ||
| C. J. Hambro | 1939–1946 | ||