She debuted in 1999 with the hit album, I Believe, and quickly gained popularity due to her strong singing skills.

[2] During the mid-2000s, Lee was one of South Korea's best-selling singers, selling more than 700,000 albums in 2004 alone despite a recession in the music industry at the time.

[3][4] In 2001, she sang the official Korean version of the Final Fantasy X song “Suteki Da Ne” in Korean, titled “얼마나 좋을까” (“Eolmana Joheulkka”).

The popularity of the album led to a limited edition (repackage) release of Grace, of which only 30,000 copies were produced.

Lee has performed the new song written by her titled "Lavender" from her new album at the wedding ceremony of her close friend, Park Kyung-lim, Kim Yoo-mi, Seo Min-jung.