Um Sang-hyun (Hangul: ???; Hanja: ???; born December 29, 1971) is a South Korean voice actor who began his career by joining Educational Broadcasting System's voice acting division in 1998.Before making his debut as a voice actor, he used to work in theaters, including performing his roles as a Japanese assassinator and a royal servant in a 1997 South Korean musical The Last Empress and working as the assistant director for South Korean musicals Gaeddongi and Moskito the same year.
In 1992, he also appeared in a South Korean independent film Opening the Closed School Gates.After his exclusive work at EBS, Um has been a freelancer since 2001.
In the early 2000s, he came to prominence after voicing Kira Yamato on the Korean dub of Mobile Suit Gundam SEED.
Since then, Um has dubbed a number of television animation series such as Chrono Crusade, Digimon Frontier, Fullmetal Alchemist, InuYasha and School Rumble.
As a result of his popularity among children audiences, the voice actor won a 2012 Nickelodeon Korea Kids' Choice Award for Favorite Voice from an Animated Movie (known as Best Voice Actor/Actress in South Korea).
He became the recipient of the award for his role as Po in Kung Fu Panda: Legends of Awesomeness, gaining 3,121 votes, which is about 38% of the entire poll.Although having been highly active as a freelancer for more than a decade, Um is also still one of the main voice actors representing EBS.
He is best known for his voicing Calcifer on the Korean dub of a Studio Ghibli animation Howl's Moving Castle, L Lawliet on the Korean dub of a Japanese television animation series Death Note, Po on the Korean dub of the DreamWorks Animation film series Kung Fu Panda and, even more recently, Poli on a South Korean animated children's television series Robocar Poli.