Semyonov (masculine), also transliterated as Semenov, Semenoff, and Semionov (Russian: Семёнов), or Semyonova (Semenova, Semionova; feminine) is a common Russian last name. It is derived from the Russian male name Semyon (related to Simeon, Simon) and literally means Semyon's. It is transliterated in Estonian and Latvian as Semjonov.
Semyonov/a
- Alexander Semyonov (disambiguation), several people
- Alexey Semyonov (disambiguation), several people
- Andrey Semyonov (disambiguation), several people
- Arkadiy Semyonov (born 1959), Russian poet
- Grigory Ivanovich Semyonov, former Socialist Revolutionary who became a Bolshevik chekist
- Grigory Mikhaylovich Semyonov, Commander of the White Army, an ataman
- Ivan Semyonov (disambiguation), several people
- Konstantin Semyonov (born 1969), former Soviet Israeli pole vaulter
- Ksenia Semyonova, Russian artistic gymnast
- Marina Semyonova, Russian prima ballerina
- Mikhail Semyonov (disambiguation), several people
- Nikolay Semyonov, Russian/Soviet physicist and chemist
- Semyon Semyonov, Russian KGB case officer
- Svetlana Semyonova, Russian rower
- Valery Semyonov
- Vladimir Semyonov (general) (born 1940), first president of the Karachay-Cherkess Republic, Russia
- Vladimir Semyonov (diplomat), Soviet diplomat and party figure
- Yulian Semyonov, Russian writer of spy fiction
- Yuno Semyonov (1899–1961), Soviet prose writer, playwright and artistic director
- Andrey Semyonov-Tyan-Shansky, Russian/Soviet entomologist and explorer
- Pyotr Semyonov-Tyan-Shansky, Russian geographer and explorer