| Oskar Hergt | |
| Order: | Vice-Chancellor of Germany |
| Chancellor: | Wilhelm Marx |
| Term Start: | 28 January 1927 |
| Term End: | 28 June 1928 |
| Predecessor: | Karl Jarres (1924) |
| Successor: | Hermann Dietrich (1930) |
| Order2: | Reich Minister of Justice |
| Term Start2: | 28 January 1927 |
| Term End2: | 28 June 1928 |
| Chancellor2: | Wilhelm Marx |
| Predecessor2: | Johannes Bell |
| Successor2: | Erich Koch-Weser |
| Order3: | Chairman of the German National People's Party |
| Term Start3: | 19 December 1918 |
| Term End3: | 23 October 1924 |
| Predecessor3: | Office established |
| Successor3: | Johann Friedrich Winckler |
| Office4: | Member of the Reichstag |
| Term Start4: | 1920 |
| Term End4: | 1933 |
| Constituency4: | Hesse-Nassau (1932–1933) Liegnitz (1920–1932) |
| Birth Date: | 22 October 1869 |
| Party: | DNVP (1918–1933) |
| Otherparty: | FKP (1902–1918) |
| Occupation: | Lawyer |
Oskar Gustav Rudolf Hergt (22 October 1869 in Naumburg – 9 May 1967 in Göttingen) was a German lawyer and nationalist politician, who served simultaneously as the minister of Justice and vice-chancellor from 28 January 1927 to 12 June 1928. Hergt attended the prestigious Domgymnasium Naumburg before studying law at Würzburg, Munich and Berlin. He worked as a Gerichtsassessor in Saxony, and as a judge in Liebenwerda. Hergt held various senior offices at the Prussian Ministry of Finance from 1904 to 1914. Previously a member of the FKP, which was dissolved after the First World War, Hergt was a founding member of the right-wing monarchist DNVP and the party's first chairman. First elected to the Reichstag in 1920, he was seen as one of the more moderate members of the party. His support for the Dawes Plan in 1924 was seen as a betrayal of the party's line and led to his replacement with the more hardline conservative Kuno von Westarp. As vice-chancellor, Hergt was the most senior DNVP politician in Wilhelm Marx's coalition government, but after losing the DNVP's leadership election in October 1928 to Alfred Hugenberg, he became an increasingly minor figure in the radicalised DNVP. After the rise of the Nazi Party, Hergt retired from politics.