Wonsool Lee (이원술) is a South Korean double bassist, bandleader, arranger and producer who won the Best Jazz Album prize at the 10th Korean Music Awards in 2013 with his first record as a leader, Point of Contact. His own releases bill him as Wonsool Lee, Discogs files him as Lee Wonsool (with Lee Won Sool and Lee Won Sul among its variants), and YouTube's automatically generated channel for his catalog spells it Lee Won sool. No source found gives a birth date or a birthplace. A Dong-A Ilbo report of July 2, 2023 describes him as 51. He is not the businessman of the same name born in 1973 whom Korean Wikipedia's article on the awards links to by mistake.

The biography on his Bugs artist page says he studied applied music at the State University of New York at New Paltz and jazz studies at SUNY Purchase, took a graduate degree at the Chung-Ang University Graduate School of Arts, and teaches in the practical music department of Baekje Institute of the Arts. Yes24's 2012 album introduction calls him a double bassist who also works as a teacher. He was already working in Seoul by 2008, when Discogs credits him with the bass on Second Rain, the second album of the piano trio Gentle Rain, led by the drummer Dukwon Seo with the pianist Song Ji-hoon; the 2012 Yes24 text describes him as a former member of that trio. The critic Choi Gyu-yong (최규용), in the essay that introduces Point of Contact, recalls hearing him in 2011 on records by Gentle Rain, the pianist Jung Jae-yeol (정재열) and a duo of Bae Jang-eun (배장은) and the guitarist Oh Jeong-su (오정수, Jean Oh).

His first album as a leader, Point of Contact, came out on January 19, 2012 (the Korean Music Awards page gives January 20). It has nine tracks and runs 49 minutes. The leader plays bass with the pianist Han Chung-wan (한충완) and Oh Jeong-su on guitar, and adds violin, cello, flute, clarinet and horn, a combination the critics heard as a Korean Third Stream record, jazz and chamber music in one frame. When the group played it live for EBS Space on April 18, 2012, the line-up was Lee on bass, Han Chung-wan on piano and keyboard, Oh Jeong-su on guitar, Kim Hong-gi (김홍기) on drums, Oh Eun-ji (오은지) on flute, Seo Bo-yeon (서보연) on clarinet, Jang Hyeong-jun (장형준) on violin, Bang Hyo-seop (방효섭) on cello and Lee Ju-yeon (이주연) on horn. In February 2013 the album won Best Jazz & Crossover Jazz Album at the 10th Korean Music Awards. The other nominees were Kang Tae-hwan's Sorefa, Kim Ji-hoon Trio's On Early Style, Lee Seon-ji's Soar and Han Ji-yeon's Ascetic, and the alto saxophonist Kang Tae-hwan took the performance prize that night. The award's citation, written by the critic Kim Hyeon-jun, says Lee had spent about ten years working faithfully behind the stage, and that the album shows him to be an enterprising musician of stubborn craftsmanship.

Into the Time followed on June 10, 2014 with ten tracks, the pianist Vian (비안), Oh Jeong-su, the trumpeter Junghyun Cho (조정현), the drummer Kim Yeong-jin (김영진) and the French harmonica player Laurent Maur. Kim Hyeon-jun's essay on the album calls it a concept album that follows one person through a single day, from "New Morning" to "A Day's Journey", and says it makes the first record's authorship plainer, since most of the composing on Point of Contact was not Lee's own. In October 2014 he joined the Icelandic trumpet and flugelhorn player Birkir Matthiasson and Oh Jeong-su for A Lonely Sight, a trio of flugelhorn, guitar and bass in which each player brought three pieces. A duo album with the pianist Lim In-gun (임인건), Assimilation (동화), appeared in September 2015.

Vian, Lee and the drummer Han Woong-won (한웅원) play together as Trio Closer, which began as the Vian Trio, played the Jarasum festival in 2012 and took its new name with the album Coexistence (2014). It has since made more Human (2016) and Contrasting Worlds (2022). Lee was also one of the musicians in the Jarasum Online Jazz Residency of 2020, whose resulting album, Jarasum Jazz Residency I (How to face my anxiety) (January 2021), was built around the theme of anxiety and led by the residency's artist and music director, the saxophonist Hyunpill Shin. He composed and arranged its opening piece, "Walking on Winter", and played double bass on others.

From the middle of the 2010s his work turned toward Korean traditional sources. He plays double bass on Kim Oki's The Great Root (on streaming services in November 2016 and on cassette in January 2017), a set of pieces drawn from the poems of Kim Su-yeong, plays electric bass on the first piece of the Gyeonggi Sinawi Orchestra's Neo Sinawi (2020), and is credited as co-producer of the vinyl compilation Arirang: The Name of Korean Vol. 8 (2021). In SINNOI he plays with the vocalist Kim Bo-ra, the geomungo player Lee Jeong-seok and the electronic musician Go Dam; the group's second album, ILLUMINATION (November 2022), won Best Global Contemporary Album at the 20th Korean Music Awards in 2023. He is music director of the Dunggi Doobop Project, which started at the 2021 Jarasum festival as a jazz-and-folk-song project and gave its first album in February 2023; the Dong-A Ilbo says he coined the band's name by joining the Korean rhythm word "dunggideok" with the jazz scat phrase "doo-bop". As a producer he made Nam Yeji's Old Songs, Tmmm (2024), nine Korean folk songs and early popular songs recast as jazz, and the singer Kang Huh Dalrim's 20th (December 2025), on which he is also arranger and bassist. He was also art director and one of the arrangers of the 2023 Jarasum Mabinogi jazz big band album.

Not published in the sources found: his birth year and birthplace, the composer credits for Point of Contact, and the itemized personnel of the Trio Closer albums and SINNOI's first album.

No text interview in which he names his influences was found, so this section sticks to what his records and the writing about them show. In the notes to "Walking on Winter" the festival describes the piece as a musical picture of tangled, contradictory states of mind that are usually thought of as coming one after another but sometimes arrive together.

Two things recur in the record. The first is a leader who arranges ensembles rather than showing off on the bass. The Yes24 essay on Point of Contact says he holds himself back and distributes the players' places carefully, so that a nine-piece band sounds like a quartet or quintet from track to track, and it contrasts the modern sound of the strings with the post-bop push of Han Chung-wan's piano and Oh Jeong-su's guitar. It singles out "The Flow of Soul" as a piece built on a short idea and free improvisation. Kim Hyeon-jun's essay on the later Into the Time reads that record as one suite, still on the surface with a tragic imagination underneath, and the players as soloists who speak briefly and never overstate.

The second is a long engagement with Korean songs and traditional sound. The Dunggi Doobop Project reworks regional folk songs, SINNOI joins folk song, geomungo, double bass and electronics, and on Old Songs, Tmmm he says, in a press statement, that the improvisation and complicated rhythm of jazz are laid over the plain and deep melodies of the old songs to give them an unusual atmosphere. In the Korean Music Awards' own wording, SINNOI's mix of the geomungo and electronic sound with Kim Bo-ra's voice and his bass is more than a simple pairing of gugak and jazz.

His arranging also reaches outside jazz: he is credited as arranger on two 2023 singles by the singer Hee-ju (희주) and a 2026 gospel single by the Salt Project, and as producer of a vinyl album by Kim Min-gyu (김민규), which Discogs files as pop. Jazz remains the center of the record: his leader albums are filed as jazz by Bugs and Apple Music, and the 2013 award was in the jazz category.