Seok-Jeong Yang is a South Korean voice actor born on January 18, 1970. He is affiliated with the Korea Broadcasting Voice Acting Division, which is the professional association for voice actors in South Korea.

Yang has built a career providing Korean-language dubbing voices for a wide range of animated series and films, primarily for Japanese anime imported into South Korea. His voice work covers numerous notable anime series. He is known for his role as Kyōsuke Hyōbu in the series Psychic Squad. In the romantic drama series Yosuga no Sora, he voiced the male protagonist Haruka Kasugano. For the historical fantasy series The Story of Saiunkoku and its second season, Yang provided the voices for two distinct characters: Kouyu Li and Sai Shou. His other prominent anime dubbing credits include Hajime Shibata in Hell Girl, Shiro Ryujoji in Jubei-Chan 2: The Counterattack of Siberia Yagyu, Taku Morisaki in the Studio Ghibli film Ocean Waves, and Kazuki Fuse in the film Jin-Roh: The Wolf Brigade.

Beyond these specific roles, his career encompasses a broad spectrum of voice acting. He is recognized for voicing major characters in popular long-running series, such as Sanji in One Piece and Shinsuke Takasugi in Gintama. His work also extends to dubbing live-action television series and films. This includes voicing Obi-Wan Kenobi in the Korean dubs of the Star Wars prequel films and the character Sayid in the television series Lost. Additionally, Yang has lent his voice to characters in video games, such as Fenix in the Korean localization of StarCraft II: Legacy of the Void.