Sergei Udaltsov
- Tiotal: Sergei Udaltsov
- Popularity: 0.001
- Aithnichte airson: Acting
- Co-là-breith: 1977-02-16
- Àite breith: Moscow, USSR (now Russia)
- Duilleag-dhachaigh: https://www.leftfront.org
- Cuideachd aithnichte mar: Сергей Удальцов, Sergey Udaltsov
