Date of birth: September 22, 1989
Position: Main Dancer, Vocalist
Hyoyeon auditioned for S.M. Entertainment at the age of 11 through SM 2000 Casting System. Hyoyeon said she auditioned because her mother brought her to the offices of S.M. Entertainment in the hopes of meeting H.O.T. Hyoyeon then danced in an audition show. In 2004, along with Super Junior's Siwon, she was sent to study Chinese in Beijing. Hyoyeon was also picked as Korea's No. 1 idol dancer on Star News.
Hyoyeon's formal dance training started in elementary school. At her neighborhood's small hip-hop school, she learned hip hop, jazz and Latin dance. In 1999, she enrolled in Winners Dance School, a famous dance school in South Korea specializing in popping, locking, animation and various other hip-hop styles. At the school she met Miss A's Min, with whom she formed the dance team Little Winners (리틀위너스). The duo performed at various showcases and was spotlighted by HipHoper.com in 2004.
Before debuting with Girls' Generation, she worked with Janet Jackson and was BoA's silhouette dancer during a performance at M.net KM Music Festival 2005.
On April 3, 2014, it was announced that Hyoyeon had been dating writer Kim Jun Hyung, age 35, for two years. SM Entertainment confirmed that the two had been a couple, but broke up on April 1 following a controversial incident where she accidentally hit him and was reported to the police for assaulting him.
In August 2016, Hyoyeon debuted in a unit for SM Station along with Min, the other half of her predebut Little Winners unit, Jo Kwon and JYP.
On December 1st 2016, Hyoyeon released her first solo song 'Mystery', through SM Station. She also starred in a second season of her reality show, 'Hyoyeon's 10 Million Likes 2'.
On June 1st 2017, Hyoyeon made her official solo debut with the song 'WannaBe'.