| László Vadnay | |
| Birth Date: | 6 June 1904 |
| Birth Place: | Budapest, Austria-Hungary |
| Death Place: | Budapest, Hungary |
| Occupation: | Screenwriter |
| Yearsactive: | 1932–1966 |
László Vadnay (1904–1967), or Ladislaus Vadnai, was a Hungarian screenwriter. He worked in the United States for a number of years before returning to Hungary.
Uncle of Adam Carolla