Yoon
- Birthday: 2004-04-14
- Place of birth: Gwangju, South Korea
- Also know as: 심자윤
Shim Ja-yun (심자윤), known under her stage name Yoon (윤), is a South Korean singer/K-pop idol. She is under High Up Entertainment. She is best known as one of the lead vocalists of the girl group STAYC.
