Korean pro (b. 1985-7-15), pupil of Kweon Kap-yong was promoted to 1 dan in 1998 and to 6 dan in 2004. Also spelled Won Seong-Jin 원성진
In 2010 Won reached the final of the 38th Myungin, losing to Park Yeonghun 3-2; in Korean ranking at the end of October he reached #2.
He won every single one of his seventeen (!) games in the 2020-21 season of the Korean Baduk League, as a member of the Celltrion team. For this feat, he was named the season's MVP.