Yoo Ki-hyun (Korean: 유기현, born November 22, 1993), known mononymously as Kihyun, is a South Korean singer and songwriter. He is a member of the South Korean boy group Monsta X under Starship Entertainment. He made his solo debut with the single album Voyager in 2022, in addition to having recorded numerous original soundtracks for South Korean television dramas.
Early life
Kihyun was born in Seoul, South Korea on November 22, 1993. He came from a family of four, which includes his father, mother, an older brother, and himself. Kihyun is also a graduate from Dong-ah Institute of Media and Arts.
Career
2014–2015: Debut and career beginnings
In December 2014, Kihyun competed in the Mnet's survival show No.Mercy. Along with six other trainees from the show, Monsta X was formed, a hip-hop idol group that debuted under Starship Entertainment, with the EP Trespass on May 14, 2015. In 2015, through the survival show, he had been featured in two of its soundtracks, for "Pillow" with Sistar's Soyou and Giriboy on January 14, and "0 (Young)" with Giriboy, Mad Clown, Jooyoung, and other remaining trainees in No.Mercy on February 4.
In May 2015, Kihyun and fellow Monsta X member Jooheon, released an original soundtrack "Attractive Woman" for KBS2's Orange Marmalade. In October, he released his first solo original soundtrack "One More Step" for the MBC's television drama She Was Pretty.
2016–2020: Original soundtracks and solo activities
Kihyun appeared as a contestant on King of Mask Singer with the name "Tell Them I'm the Dragon King" on January 3, 2016. He won the first round against Apink's Namjoo, known as "Good Daughter Shim Cheong". On the second round of the competition, he lost to Lim Jeong-hee, known as "Rolled Good Fortune", with the difference of three votes.
In April, Kihyun became an MC for MBC Dramanet's Tasteful Beauty Plus. He participated with Son Tae-young and Kim Ji-min, as one of the beauty information and tips experts.
Kihyun sung the acoustic version of "The Tiger Moth" for the soundtrack for MBC's drama Shopping King Louie, which was released on October 27.
In June 2017, an original soundtrack titled "I've Got A Feeling" for SBS' drama Suspicious Partner was released.
In May 2018, Kihyun recorded "Can't Breathe" for MBC's Partners for Justice with fellow Monsta X member Jooheon, and in June, he also recorded "Love Virus" for tvN's drama What's Wrong with Secretary Kim together with WJSN's Seola.
For Monsta X's album All About Luv, Kihyun participated in writing and producing of three songs, including "Who Do U Love?" featuring French Montana (and its remix by will.i.am), "Middle of the Night", and "Beside U". He had previously co-written "I Do Love U" from Take.1 Are You There? with three other members, as well as co-written and produced the song "No Exit" for their debut EP Trespass.
In April 2020, Kihyun released a song for the soundtrack of KBS2's Welcome, titled "Again Spring", and then a song for KBS2's Do Do Sol Sol La La Sol, titled "To Be With You", on October 7. In October, Kihyun had a solo stage for M Studio on M Countdown, where he performed a cover of the song "Bad" by Christopher.
2021–present: Solo debut with Voyager and other solo activities
In February, Kihyun released a song for the soundtrack of the drama Replay: The Moment, titled "O.M.O.M.". He was praised for his work in the drama, particularly his voice was able to express the "sweetness and softness" that complemented the drama.
In August, Kihyun appeared as a special guest on Naver Now's Night Studio, where he sang covers of several songs, including "Middle of the Night" by Monsta X and "Radioactive" by Imagine Dragons, with a live band. He also became a new DJ for Naver Now's Midnight Idol, alongside group member I.M.
In September, Kihyun appeared again as a contestant on King of Mask Singer's special duet episode for the 2021 Chuseok holiday. Kihyun also paired up with a co-label solo artist Jeong Se-woon as the "Cheongdam-dong Sworn Brothers". They lost in the first round against MeloMance's Kim Min-seok and actor Kim Woo-seok as the "Brave Brothers".
He made his solo debut with the single album Voyager, along with the lead single of the same name, contributing to the lyrics of the song ", (Comma)" on March 15, 2022. Kihyun tested positive for COVID-19 on March 30.
On August 4, Kihyun released a song for the soundtrack of the webcomic After School Lessons for Unripe Apples, titled "Is This Love".
On September 16, he appeared and performed in the music festival KPOP LAND 2022, to commemorate love, peace, and a better world, in Jakarta, Indonesia.
On October 14, Kihyun performed in the KCON 2022 Japan, held at Ariake Arena in Tokyo. On October 24, he released his first EP Youth, along with the lead single of the same name. On October 25, Kihyun was selected as the sole host for Naver Now's new live show PLAY!, starting on November 7.
On November 12, he released a song for the soundtrack of the new SBS' Friday-Saturday drama The First Responders, titled "Fire".
In January 2023, Kihyun had a pictorial and an interview for the fashion magazine Arena Homme + Korea.
In April, he became a fixed panelist for JTBC's current affairs and liberal arts program Han Moon-cheol's Black Box Review. On April 16, Kihyun and Joohoney participated in the soundtrack of TVING's original Our Game: LG Twins, titled "Awake". It is a song about overcoming difficulties by cheering each other on and raising hope, which combines rock and hip hop, and contains a moving theme of turning adversity upside down. They also participated in its pitch and theta for victory before the game series against Doosan Bears.
On May 7, he released a song for the soundtrack of the television series Tale of the Nine Tailed 1938, titled "Full Moon". On May 28, Kihyun performed at the Peak Festival 2023, held at Nanji Hangang Park in Seoul.
In June, he attended the 2023 Seen Festival in Hội An, Vietnam. On June 22, Kihyun attended the Korea-Vietnam Cultural Exchange Night, held at Vietnam National Convention Center, as "K-pop Representative Singer". It was a place to enjoy K-pop and V-pop together, to strengthen cultural consensus between the two countries and promote friendship for the future generations.
In March 2025, he held a free fan event after his military discharge.
On May 25, Kihyun performed at the Peak Festival 2025, held at Nanji Hangang Park in Seoul.
On June 28, he performed at the Someday Festival, in commemoration of its 10th anniversary, held at KINTEX in Ulsan.
In October, it was announced that Kihyun will be one of the judges for the vocal survival show Veiled Musician.
In April 2026, it was announced that he will perform for third consecutive year at the Peak Festival 2026 on May 24, to be held at Nanji Hangang Park in Seoul. On July 7, Kihyun released his second EP Borderline, along with the lead single "So Good". The lead single's English version was released on July 24.
Military service
Kihyun enlisted for his mandatory military service as part of the military band, with 25th Infantry Division at Yangju army base in North Gyeonggi Province on August 22, 2023. In February 2024, he was featured in the Korean military magazine Kookbang Ilbo. Kihyun was officially discharged on February 21, 2025.
Musical style and influences
Kihyun has been described to possess a soulful pop rock voice that is "refreshing yet sexy". He is also noted for his high-pitched ad libs.
Kihyun had cited singer Harry Styles as his role model.
Public image and impact
Kihyun has been known for his singing ability, recording numerous television dramas soundtracks and vocal cover videos of various genres. As the main vocalist of Monsta X, he has captivated the K-pop fans by showing off his live skills despite the group's strong performances, which also earned him the honorifics "K-pop God" and "Vocal God".
In October 2019, an official statement from Kakao M revealed that Monsta X…