Ryu Da-in (; born September 29, 2000) is a South Korean model and actress. She made her debut in the JTBC drama, 18 Again in 2020.
Ryu was born in Busan, South Korea and is an only child. She completed her high school education through the General Educational Development examination.
Ryu used to be a model and worked with YG Kplus. In 2023, she signed an exclusive contract with Aground. In June 2025, Ryu signed an exclusive contract with Alien Company.
In March 2024, it was revealed that Ryu is in a relationship with actor Lee Chae-min. The two met on the set of Crash Course in Romance (2023).