Main article: Fin.K.L
She started her career as part of the Korean pop girl group Fin.K.L. As the oldest member, she would become the leader of the group. Lee was discovered while taking sticker pictures with her friends and was actually the last to join Fin.K.L., just before their debut in January 1998. Fin.K.L. debuted officially on May 22, 1998 with their first single "Blue Rain." It was received quite well. The second release from their first album, To My Boyfriend, became the first of their multiple number one hits. Fin K.L. became one of the most popular and successful Korean groups of all-time, rivaling fellow popular girl group S.E.S..[edit] Establishing a solo entertainment career
A year after Fin K.L.'s fourth album Forever, her solo album was released at the end of 2003, entitled Stylish...E. The singer nearly swept the 2003 Daesangs, the most prestigious South Korean music award, winning more than seven of them, including three of the four most prestigious Daesangs. STYLISH...E hyOlee sold over 144,182 copies in South Korea alone, according to the Music Industry Association of Korea in 2003.[1] Her popularity in her various activities eventually was dubbed as the "Hyori Syndrome" in South Korea, and the Korean Media nicknamed 2003 "The Year of Hyori" as she was rarely out of the news all year.[2]Lee Hyori has also appeared as the lead female actress in the SBS drama Three Leaf Clover co-starring opposite Ryu Jin, Kim Jung Hwa, Kim Kang Woo and Lee Hoon. However, the ratings were continually low, and it ended after 16 episodes. On August 8, 2005 she co-hosted the annual Korean Music Festival for the second year running.
In February 2006, Lee released her follow up album, Dark Angel. The first single, "Get Ya", was controversial as the songwriters of Britney Spears' single "Do Somethin'" accused the "Get Ya" songwriters of plagiarism.[3]