Lee Sungmin was born January 1, 1986; he is mostly known as Sungmin. He is a singer, actor, dancer, DJ and member of Super Junior. He is a regular DJ of Reckless Radio and is one of the two members in Super Junior who performs Chinese martial arts, the other being Han Geng; He currently attends Seoul Institute of the Arts, majoring in Broadcasting and Television Entertainment.

Lee Sungmin became a trainee under SM Entertainment after he won first place at the 1st SM Youth Best Selection Best Outward Appearance in 2001. A year later Sungmin, along with Eunhyuk, Xiah Junsu, Typhoon, Rose, and Attack, who were placed in one project group, made a brief appearance in a show called Heejun vs. Kangta Battle of the Century Pop vs. Rock. However, in 2003 the group was separated because Xiah Junsu debuted as a member of TVXQ and Typhoon, Rose, and Attack debuted as members of TRAX. Sungmin, however, stayed with Eunhyuk and both of them debuted as members of Super Junior two years later.

 A year later after Super Junior's debut, Sungmin appeared in the SBS Banjun Theatre drama Finding Lost Time as a guest star acting alongside TVXQ's Micky Yoochun. In early 2007, Sungmin was placed in the six-piece Super Junior subgroup, Super Junior-T, and debuted on February 25, 2007.