Zahn is a surname. Notable persons with the surname include:
- Friedrich Wilhelm Zahn (1845-1904), German pathologist
- Johann Zahn (1631-1707), German canon who wrote on the camera obscura and who invented an early camera
- Johannes Zahn (1817-1895), German musicologist and theologian who developed a taxonomy of Lutheran hymns and melodies
- Paula Zahn (born 1956), American newscaster
- Peter von Zahn, (1913–2001), German author, filmmaker, and journalist
- Steve Zahn (born 1967), American actor
- Theodor Zahn (1838-1933), German biblical scholar
- Timothy Zahn (born 1951), American science fiction novelist