Lee Seung Hwan, known professionally as Seo Kang Joon, is a South Korean actor, model, singer, and former member of 5URPRISE (서프라이즈). He graduated from Sanbon High School and later obtained an associate's degree in Acting from Dong Seoul University.

Before debuting, he worked as a part-time model to pay for college. In September 2013, Fantagio (판타지오) launched a new project group called 5URPRISE. The group members were selected through Fantagio's "Actor′s League," a program for discovering aspiring actors, and were trained for two years before making their entertainment debut.