Seo Chae-hyun, also known as Chaehyun Seo, is a South Korean professional rock climber who specializes in competition climbing. She won the overall 2019 World Cup title in competition lead climbing in her senior debut season. In August 2021 she represented South Korea at the 2020 Summer Olympics, where she was a finalist, and later that year won the IFSC World Championship in lead.

The 2021 IFSC Climbing World Championships was the 17th edition of the competition climbing event. It was held in Moscow, Russia from 16 to 21 September 2021, alongside the 2021 IFSC Paraclimbing World Championships.