Pyatnitsky (surname)
Pyatnitsky (Russian: Пятницкий; masculine) or Pyatnitskaya (Пятницкая; feminine) is a Russian surname. It is shared by the following people:
- Andrey Pyatnitsky (b. 1967), Russian association football player
 - Konstantin Pyatnitsky (1864–1938), Russian journalist, publisher, and memoirist
 - Mitrofan Pyatnitsky (1864–1927), Russian musician, founder of the Pyatnitsky Choir
 - Osip Piatnitsky (Pyatnitsky) (1882–1938), Soviet politician
 - Valery Pyatnitsky (b. 1962), Ukrainian politician