Youn Sun Nah (나윤선) is a Seoul-born jazz vocalist who has built her career between Paris and Seoul and is among the best-known Korean jazz singers abroad. She was born on August 28, 1969. Korean sources and Wikipedia romanize her name as Na Yoon-sun, and her earliest Korean releases were billed Nah Youn Sun, but her records on ACT and Warner, her own website and Discogs all use Youn Sun Nah, the spelling used here. She has made 13 studio albums since 2001, the latest being Lost Pieces (February 2026), and Korean press describes her as one of the leading figures of Korean jazz singing. A 2007 profile in the Korea JoongAng Daily already noted that she lived in both Paris and Seoul and was a force on the music scenes of Korea and France.

She grew up in a musical family. Her father, Na Young-soo, was a conductor who led the National Chorus of Korea, and her mother, Kim Mi-jung, is a singer and musical actress. She learned piano as a child but concentrated on her general studies, and in 1992 she took a degree in French literature at Konkuk University in Seoul. The next year the Korean Symphony Orchestra invited her to sing gospel, which gave her first steps on stage and on record: Korean Wikipedia lists two gospel albums with the orchestra from 1994. After that she was cast in musicals. Wikipedia says she made her acting debut in Subway Line 1 at the Hakchon Theater after the company's president, Kim Min-gi, noticed her. In the 2007 JoongAng interview she described a supporting part in that production as the step that led her to France. She was not convinced the musical stage was her path, and decided to go back to school and study music and singing seriously.

In the autumn of 1995 she moved to Paris. She enrolled at the National Music Institute of Beauvais, at the Nadia and Lili Boulanger Conservatory and at the CIM, a school for jazz and contemporary music, and her official biography says it was at the CIM that the decisive moment came. Wikipedia says she taught at the CIM in 2000 and 2001. French Wikipedia says she began playing in Paris clubs in 1996 and 1997 and was noticed by the bassist Jacques Vidal, who invited her onto his album Ramblin' (1999). Competitions brought her first prizes: Korean Wikipedia lists second prize at the Montmartre jazz festival (1998) and a grand prize at the Saint-Maur jazz competition and a special jury prize at the La Défense competition (both 1999). At the CIM she also met the bassist Yoni Zelnik and the drummer David Georgelet, who joined the quintet she formed in Paris.

Her first album, Reflet, was issued in South Korea by Sony Classical on June 13, 2001. The quintet then recorded two albums for the Paris label In Circum Girum at Studio La Buissonne in Pernes-les-Fontaines. Light for the People (recorded in February 2002) has Guillaume Naud on piano, David Neerman on vibraphone, Zelnik on bass and Georgelet on drums, and for So I Am... (recorded on February 2 to 4, 2004) Benjamin Moussay took over the piano chair. In between came Down by Love (Sony Classical, 2003), which won the Best Crossover Album award at the first Korean Music Awards in 2004. In 2005 she took the grand prize at the Jazz à Juan Révélations competition in Juan-les-Pins, and the same year Korean Wikipedia lists a young-artist award from the Ministry of Culture and Tourism. A 2005 EMI Korea release, Nah Youn Sun with Refractory, paired her with the French group Refractory, whose track "Road" with her voice had appeared on the compilation Buddha-Bar V in 2003. German Wikipedia says Wynton Marsalis invited her to the Jazz at Lincoln Center series, and Zelnik's biography places a Lincoln Center appearance with the quintet in 2007.

Memory Lane, issued by Seoul Records on April 10, 2007, was a deliberate pop project. It was recorded in Copenhagen in late 2006 and produced with the Danish pianist Niels Lan Doky and the Korean bassist Jung Yeol Kim, with Mads Vinding on bass, Alex Riel on drums, Mikkel Nordsø on guitars and Didier Lockwood as violin guest. Several songs are by Korean composers, among them the pianist Kim Kwang-min, credited by Discogs with the music of "Han River". She told the JoongAng Daily at the time that she had removed the improvisation and kept to melody and main chords, and that she agreed the record was very pop.

From 2008 the centre of her career moved to the German label ACT. Voyage was recorded on June 2 to 4, 2008 at Nilento Studios in Gothenburg, Sweden, with the Swedish bassist Lars Danielsson, who produced it and played bass, cello and melodica, the guitarist Ulf Wakenius, the trumpeter Mathias Eick and the percussionist Xavier Desandre Navarre. It came out in Korea in September 2008 and on ACT in 2009, and won the jazz album prize at the Korean Music Awards in 2009. A voice and guitar duo with Wakenius toured Europe, Asia and Canada; French Wikipedia counts more than 60 concerts in about 20 countries. In 2009 France made her a Chevalier of the Order of Arts and Letters.

Same Girl (ACT, September 2010), again with Danielsson, Wakenius and Desandre Navarre, made her name across Europe. Its tracks include "My Favorite Things", Metallica's "Enter Sandman", the Korean folk song "Kangwondo Arirang" and her own "Uncertain Weather". According to her official biography it won the Académie du Jazz prize for best international vocal jazz album of 2010, the ECHO Jazz award for best international female singer in 2011 and the Korean Music Awards jazz album prize in 2011, and it was certified gold in France in 2012. She sang for the heads of state at the G20 summit in Seoul in November 2010.

Lento (ACT, March 2013) was recorded at Nilento Studio on October 31 to November 2, 2012 with Danielsson, Wakenius, Desandre Navarre and the accordionist Vincent Peirani, who also co-wrote two of its songs. It opens with the title piece, built on a Scriabin prelude, adds Nine Inch Nails' "Hurt" and "Ghost Riders in the Sky" to her own songs, and closes on the Korean folk song "Arirang". It was gold in Germany in 2013 and in France in 2015, and it won the jazz album prize at the 11th Korean Music Awards, held on February 28, 2014 at the Yes24 Move Hall in Seoul, according to the TenAsia report. Her biography counts about 500 concerts around the world between 2009 and 2015. In 2013 she was president of the jury of the Montreux Jazz Festival's vocal competition, on February 23, 2014 she sang at the closing ceremony of the Sochi Winter Olympics, and in 2015 the National Theater of Korea made her artistic director of its Yeowoorak festival of traditional Korean music. Korean honours of this period include the Prime Minister's commendation for popular culture and arts (2012) and the Sejong Culture Award (2014).

For She Moves On (ACT, May 19, 2017) she went to New York. The record was made at Sear Sound in December 2016 with the keyboardist Jamie Saft as producer, the guitarist Marc Ribot, the bassist Brad Jones and the drummer Dan Rieser, and it covers songs by Paul Simon, Lou Reed, Jimi Hendrix, Joni Mitchell and Fairport Convention beside a few of her own. On April 30, 2017 she took part in the International Jazz Day all-star concert in Havana, singing "Bésame Mucho" with the Lebanese pianist Tarek Yamani; her official biography names Herbie Hancock, Regina Carter, Esperanza Spalding and Antonio Sanchez among the musicians she shared the stage with that night.

In 2019 she signed with Arts Music, the Warner Music Group division, and released Immersion (March 2019), her tenth album, produced and largely arranged by Clément Ducol with the multi-instrumentalist Pierre-François Dufour. It mixes her originals with songs by Marvin Gaye, George Harrison, Johnny Cash's "God's Gonna Cut You Down", Leonard Cohen's "Hallelujah" and "Sans Toi" by Michel Legrand and Agnès Varda. On November 28, 2019 the French Ministry of Culture promoted her to Officier of the Order of Arts and Letters. In December 2020, with stages closed by the pandemic, she took the artistic direction of Arirang: The Name of Korean Vol. 8 (Korean Traditional Performing Arts Foundation, 2021), on which Korean traditional musicians and European jazz players, among them Vincent Peirani, Andy Sheppard and Samuel Blaser, recorded from a distance; Discogs credits her as music director.

Waking World (January 28, 2022) was built mostly on her own songs, written and produced with Axel Matignon, with Thomas Naïm on guitar and banjo, Laurent Vernerey on bass, Xavier Tribolet on keyboards and drums, the trumpeter Airelle Besson, the cellist Guillaume Latil and the violinist Héloïse Lefebvre; an 18-month tour followed. Elles (January 26, 2024), a duo record with the American pianist Jon Cowherd, was her tribute to women's voices, including singers who marked her own path, and during its tour pianists including Benjamin Moussay, Tony Paeleman and Bojan Z shared the stage with her.

Her 13th album, Lost Pieces, was released worldwide on February 20, 2026 (February 23 in Korea). All 11 songs are her own words and music, and the record was made with the guitarist Matthis Pascaud, the bassist Laurent Vernerey, the drummer Raphaël Chassin, the pianist Tony Paeleman, the cellist Guillaume Latil and other guests including the French saxophonist Christophe Panzani. A press release for the album says it reached number one on a European jazz chart on release and that the French magazine Télérama gave it its top rating. On May 29, 2026 she played it at the Jirisan Jazz Festival Spring at the Cheoneunsa temple in Gurye, South Korea, and a Paris concert with Pascaud, Jones and Chassin is listed for November 25, 2026 at La Seine Musicale in Boulogne-Billancourt. The drummer Guilhem Flouzat says in his own biography that he has been a longtime sideman for her; no recording credit confirms it.

Jazz is the framework of her career, but her repertoire is unusually wide. English Wikipedia says she knew little of jazz until she began studying it in Paris, that she had already shaped her own way of singing, and that before then she had sung everything from classical music to rock, so it names no historical jazz singer as a model. Her records follow that: Metallica and Nine Inch Nails songs and Jimi Hendrix on the ACT albums, Korean folk songs ("Arirang", "Kangwondo Arirang"), French chanson, Joni Mitchell, Paul Simon and George Harrison, and, from Waking World on, mostly her own writing. ACT's biography stresses her wide vocal range and expressiveness, and on her records she also plays kalimba and a music box.

Jazz is her main setting, with ACT, the Académie du Jazz and the ECHO Jazz behind her and the jazz categories of the Korean Music Awards. Her pop side is real as well. Memory Lane (2007) is a self-described pop project, the Discogs entries for Down by Love, Moments and Waking World also carry a pop tag, and the 2004 Korean prize she won was for Best Crossover Album, not a jazz category. The line-ups behind her are usually small: a voice and guitar duo, a quartet with accordion and bass, a piano duo, or a rhythm section with guitar and cello.