Dong Seo (동서) is a South Korean company. It was founded in 1986 and began publishing Western PC games in September 1990. Among those were adventure games developed by LucasArts, Sierra, and other notable companies. In 1992 they translated Eye of the Beholder into Korean.

Dong Seo started developing games in 1994, at first focusing on strategy games set in historical Korea, and later switching to online games. The company's CEOs were Yun Weonseok (until 1998), Gu Jaehong (May-August 1998), O Sanghyeon (September 1998 - February 2001), and Yun Weonbin (from February 2001).