| Károly Hieronymi | |
| Order: | Minister of the Interior of Hungary |
| Term Start: | 17 November 1892 |
| Term End: | 15 January 1895 |
| Predecessor: | Gyula Szapáry |
| Successor: | Dezső Perczel |
| Birth Date: | 1 October 1836 |
| Birth Place: | Buda, Hungary |
| Death Place: | Budapest, Hungary |
| Profession: | engineer, politician |
| Party: | Liberal Party, Party of National Work |
Károly Hieronymi (1 October 1836 – 4 May 1911) was a Hungarian engineer and politician, who served as Interior Minister between 1892 and 1895. He was a supporter of former Prime Minister Kálmán Tisza. As Minister of Trade he modernized the train services, for the Hungarian State Railways he nationalized the Budapest-Pécs, the Duna-Dráva and the Zagreb-Karlovac railway lines. He insured the independence of the railway goods turnover aiming at the seaports and its tranquillity.
In Budapest there is a street named after him. His grave is in the Kerepesi Cemetery.