• Birthplace: Incheon, South Korea
• Age: 34
• Height: 160
• Weight: 49
• Website: http://snsd.wikia.com/wiki/Hyoyeon

Kim Hyo-yeon, better known as Hyoyeon (효연), is a South Korean singer, dancer, and actress. She is a member of the K-pop girl group, Girls' Generation, as the main dancer, main rapper and supporting vocalist.

Hyoyeon was born in Incheon, South Korea. She is ambidextrous and grew up with her parents and her younger brother Kim Min-gu.

During her childhood, Hyoyeon attended a small neighborhood dance class, learning Jazz, Hip-hop, and Latin dance. In 1999, she began attending Winners Dance School, a famous dance school in South Korea, which taught popping, locking and other Hip-hop dance styles.

Hyoyeon auditioned to SM Entertainment at the age of 11 through the SM 2000 Casting System and passed her audition which was dancing, thus she became a trainee under SM and trained for her career for six years and one month before debut. Hyoyeon revealed she had no intentions to audition, however, her mother was a fan of S.M. Entertainment's boy band H.O.T. and brought her to the offices in the hopes, perhaps, of seeing them. In 2004, she was sent to study Mandarin Chinese and to learn more about Chinese culture in Beijing, China with labelmate, Choi Siwon.

Hyoyeon also received dance instruction from the Electric Boogaloos, and other top dance choreographers such as Poppin Seen, Kwon Seon-jin, Shim Jae-won and several others.

Predebut, Hyoyeon also worked with Janet Jackson and was BOA's silhouette dancer during a performance at the M.net Music Festival 2005, she furthermore was a member of the dance group, Little Winners, with current Miss A member, Min, the duo danced at various showcases.

Hyoyeon is a sub vocalist and main dancer, in the girl group, Girls Generation, which debuted in 2007. She is well known for her brilliant dance ability, earning her the nickname, Dancing Queen.

Hyoyeon made a cameo, acting in the drama, Oh! My Lady and was on the second season of Invincible Youth, alongside band mate Sunny. Hyoyeon also joined the second season of the Korean Dancing with the Stars, in 2011, her dance partner was Kim Hyung Seok, and they came second place in the competition. Hyoyeon was named Topshop's Asia Ambassador in May 2013 and was a member of the one hit group, Younique Project and they released the single "Maxstep" to promote the Hyundai brand. She has appeared on many shows and was a guest on the show, Jessica, and Krystal. Hyoyeon furthermore featured in the music video for Shake That Brass by Amber featuring Taeyeon and the music video for Whoa Ah! by VASCO.

Hyoyeon in 2015, starred in a reality television show called Hyoyeon's One Million Likes, she also released her own book, Hyo Style. And on February 3, 2016 was a special MC on the Television show, Get It Beauty. In May 2015, became a cast member on the Korean Chinese television show, Star Advent.

In August 2016, Hyoyeon debuted in a group called Triple T, with Jo Kwon from 2PM and Min from Miss A, the trio released the song, "Born To Be Wild" featuring Park Jin-young. In December 2016, Hyoyeon released a solo song, "Mystery" under SM Station.

On June 1st, 2017, Hyoyeon released the single "Wannabe" featuring rapper, San E.

In 2014, it was revealed that Hyoyeon in the past two years, had been dating 35-year-old writer Kim Jun Hyung. The two however on April 1, 2014, broke up because of an incident where Hyoyeon accidentally hit him and she was reported to the police for assaulting him.

Hyoyeon is close to Miss A's Min, her band-mate Seohyun who she also shares her dorm with f(x)'s Amber.