Yoosun Nam (남유선) is a South Korean alto and soprano saxophonist and composer who trained in Seoul, at Berklee College of Music and at New York University's Steinhardt school, lived in New York for several years, and has worked in Seoul since returning. She has made four albums as a leader: Light of the City (2014), Strange, But Beautiful You (2018), Things We Lost & Found (2021) and The Moments of Life, released on October 27, 2026. The second and third were each nominated for a Korean Music Award in the jazz categories, in 2019 and in 2022.

Her date of birth is not published. All About Jazz's reviewer Hrayr Attarian calls her a Seoul native, MusicBrainz lists Anyang, a city just south of Seoul, as her birthplace, and her own biography says only that she is from South Korea. Her name is printed in several forms. Her website, All About Jazz and the credits of her newest album use Yoosun Nam; her first album was released digitally as the Yoosun Nam Quintet; her later releases are filed under Nam Yoosun on Apple Music and Deezer, and one cover prints Nam Yoo Sun. Korean press and her own Korean posts write 남유선, and the Seoul daily Newstomato romanizes it Nam Yu-sun. This profile uses Yoosun Nam, the form on her website and on her latest credits.

According to her biography, she began studying classical piano and voice at the age of nine and won several vocal competitions in South Korea, then started listening to jazz in high school. She took up the saxophone at 19, while she was studying computer science at Seoul National Women's University, and in 2002 transferred to the Seoul Institute of the Arts, where she says she received an award from the Applied Music department. She was then admitted to Berklee College of Music, where her biography says she studied with George Garzone, Bill Pierce and Darren Barrett and received the Joseph Viola award from the woodwind department. In 2011 she moved to New York to study for a master's degree in jazz at NYU Steinhardt. Her biography names the faculty she studied and performed with there as Joe Lovano, Dave Pietro, Gil Goldstein, Kenny Werner, Alan Ferber and Ralph Alessi, and in 2020 Newstomato described her as a Berklee and NYU alumna who had lived in New York for a long time.

In New York she led her own group in clubs and recorded Light of the City with a quintet: Kyumin Shim on piano, Keisuke Matsuno on guitar, Carlos De Rosa on bass and Jesse Simpson on drums, with the tenor saxophonist Chris Cheek as a guest on three tracks. All eight pieces are her own, and she plays alto and soprano. All About Jazz ran three reviews, by Hrayr Attarian on December 4, 2014, Edward Blanco on December 8, 2014 and Ian Patterson on March 6, 2015. Her website lists a release night at Cornelia Street Cafe in New York on January 7, 2015, with the saxophonist Adam Kolker as a special guest, then quintet dates at the WhyNot Jazz Room in April and May 2015 and at ShapeShifter Lab in Brooklyn on October 10, 2015. Her website also says CUNY TV broadcast a half-hour of a quintet concert on August 15, 2015; the series is Brooklyn College Presents, and the broadcast was titled Yoosun Nam Quintet Live: Light of the City.

Her path back to Korea can be followed through her own listings. A video of her piece "L Train" was filmed at Yagi Studio in Seoul on July 14, 2015, with the drummer Soojin Suh in the band. In early 2016 her website describes a five-night tour of Korea with her New York guitarist Matsuno and a Korean rhythm section, and says the EBS television channel invited her quintet to appear as one of its 2016 "New Jazz Faces of Korea", broadcast in March 2016. She was still playing in New York in January 2017 and in Seoul in February 2017. By the autumn of 2018 almost every date on her website is in Seoul, among them sets at the clubs Positive Zero and All That Jazz, a Seoul Forest jazz festival date on October 7 and a Jeju island festival date on October 20. The critic Kim Hyun-joon, in the liner essay on her second album, writes that she wound up her New York life and came home, and that this is when she found her own identity as a composer.

Strange, But Beautiful You was released on October 30, 2018 by Mirrorball Music, a Korean label. It is a quintet record with Yoon Jihee on piano and keyboard, Oh Jinwon on guitar, Hoo Kim (김영후) on bass and Kim Youngjin on drums, with Do Jaemyung narrating on two tracks, and all ten pieces are hers, including "L Train" from her 2015 video. The 16th Korean Music Awards nominated it for Best Jazz Album; the nominations were announced on January 29, 2019, and the other nominees were Youngjoo Song, Bongwool Lee, Sunji Lee and Sumin Jung. Sunji Lee's Song of April took the prize. Her quintet played the 16th Jarasum Jazz Festival on October 4, 2019, in the festival lounge, and the festival published a video greeting from the group.

In 2020 she appeared in episode 20 of the Improv Exchange podcast, released on August 2, 2020. In October 2020 Newstomato previewed Charlie Parker@100, a concert planned for October 18 at Pomtech Works Hall in Seoul to mark the centenary of Charlie Parker: she and the alto saxophonist Daniel Ko were to take turns in the role of Parker, he in a traditional first half and she in a second half that used Ableton Live to reshape Parker's own tunes, with Kim Eun-young on piano, Jeon Chang-min on bass and Song Jun-young on drums. The article does not report on how the evening went.

Things We Lost & Found followed in October 2021. She plays alto and soprano saxophones and electronic sound effects on it, with Sim Gyumin (the Kyumin Shim of her first album) on Prophet synthesizer and piano, Kim Youngjae on piano, Ryu Hyunggon on bass and Han Injip on drums, and all eight pieces are hers. A release concert took place at Belloju in Hongdae, Seoul, on October 15, 2021, supported by the Seoul Metropolitan Government and the Seoul Foundation for Arts and Culture. The album was a nominee for Best Jazz Instrumental Album at the 19th Korean Music Awards in 2022, where Jihye Lee's orchestra won with Daring Mind.

Her own biography, posted in December 2023, lists teaching at the Seoul Institute of the Arts and the Dong-ah Institute of Media and Arts and invitations to the Seoul Forest, Jarasum and Ulsan jazz festivals, and says her studio is in Yangjae-dong in Seoul. She gives online saxophone lessons through the Korean channel Vlumm (블럼), and an Arirang Radio live session of "Brave" was posted in August 2023. Her fourth album, The Moments of Life, came out on October 27, 2026 on D Ocean Music, a quartet record with Chaesun Yim on piano, Hyunggun Ryu on bass and Sunbean Kim on drums, with a string group, Phil String, on three tracks arranged by Eunhye Oh. Its title track is "Youth".

One more credit belongs to her story, with a caveat on the spelling. Challenge Records' description of the 2018 big-band album Tschüss Jazz Era by the Korean group Jungsu Choi Tiny Orkester names an alto saxophonist as Yusun Nam, beside Hachul Song on tenor, and the Bimhuis in Amsterdam, which listed the band for December 29, 2017, printed the name as Yuseon Nam. Neither source ties that name to her, and the label's own personnel list gives different saxophonists, so it is recorded in the discography as a possible credit rather than a confirmed one.

She writes modern mainstream jazz for a small group in which the melody carries the music. The critics on her first record heard a leader with a warm, lyrical alto, an agile technique and a quintet that kept close to straight-ahead jazz while adding contemporary touches, and two of them found it more polished than surprising. Her eight originals include a piece titled for Chagall, a blues and a funky, humorous closer, and Blanco writes that the lights of New York at night inspired the title piece.

Kim Hyun-joon, writing about the second album, calls her a melody maker whose tunes come from daily life and who treats herself, her world and jazz itself as strange and beautiful. The third album adds electronics and a new sound-world to what the label's critic describes as strong writing and efficient playing, and her Parker project in 2020 pointed the same way, using Ableton Live to bend the saxophone's sound. The note on the Melon page for the 2026 album places it in post-bop and describes it as a sequence of life stages, from birth to youth.

The sources available do not name her influences. The Newstomato piece treats Charlie Parker as a central figure for her and for Ko, and her teachers at Berklee and NYU are named above.