| Wilhelm Buck | |
| Birth Date: | 12 November 1869 |
| Birth Place: | Bautzen, Kingdom of Saxony |
| Death Place: | Radebeul, Soviet Occupation Zone |
| Office1: | Minister-President of the Free State of Saxony |
| Term Start1: | 1920 |
| Term End1: | 1923 |
| Predecessor1: | Georg Gradnauer |
| Successor1: | Erich Zeigner |
| Office3: | Member of the Riechstag |
| Term Start3: | 1920 |
| Term End3: | 1924 |
| Office4: | Member of the Imperial Riechstag |
| Term Start4: | 1913 |
| Term End4: | 1918 |
| Office5: | Member of Dresden City Council |
| Term Start5: | 1908 |
| Term End5: | 1917 |
| Party: | Social Democratic Party of Germany (1932– & 1887–1926) Old Social Democratic Party of Germany (1926–1932) |
Johann Wilhelm Buck (12 November 1869 in Bautzen, Kingdom of Saxony – 2 December 1945 in Radebeul) was a German politician and representative of the Social Democratic Party[1] and the splinter party, Old Social Democratic Party of Germany. From 5 May 1920 to 21 March 1923, he was minister-president of the Free State of Saxony.[1]