Sergei Rachmaninoff (1873–1943) was a Russian composer, pianist, and conductor.
Rachmaninoff or Rachmaninov may also refer to:
- Rachmaninoff (crater), a crater on Mercury
- Rachmaninoff (vodka), a German vodka
- Ivan Rakhmaninov (1753–1807), Russian publisher, translator and educator
- Yuri Pavlovich Rachmaninov (1936–2007), Soviet and Russian scientist, great-nephew of Sergei Rachmaninoff