Sydney Lassick
- Born
- 22 July 1922 (80 years old)
- Passed away
- 11 April 2003
- Place of birth
- Chicago, Illinois, USA
- Gender
- Male
Sydney Lassick (July 23, 1922 – April 12, 2003) was an American character actor perhaps best known for his role as Charlie Cheswick in the feature film One Flew Over the Cuckoo's Nest.
