Joonghwa Jung (정중화) is a South Korean jazz trombonist, bassist, composer and teacher based in Seoul. He began as a double bassist, working in Japan, New York and Seoul, and took up the trombone in his thirties; since 2014 he has recorded mainly as a trombonist, leading a quintet and writing most of his own material. Korean streaming services list seven albums under his name, from a 2007 duo with a guitarist to a 2021 set of vocal pieces, and his label's biography mentions an earlier first album, JUN in NY. He is the son of the saxophonist and arranger Jung Sung-jo, and since March 2018 he has been a full-time faculty member of the practical music program at Seoul Institute of the Arts (서울예술대학교).

His name is spelled several ways. His label, Huks Music, titles its videos "Joonghwa Jung", and Discogs files the same spelling as a variation of the Hangul entry 정중화; that is the form used here. The covers of Autumn Rain and Moon Dance print "Jung, Joong Hwa", and Korean press and reference works write Jung Joong-hwa.

Very little is published about his early life, and no source found gives his birth date or birthplace. A Yonhap News feature of December 10, 2014 gives his age as 43 and says he started the double bass at 21. The EBS Space listing for a 2004 concert says he went to Japan in 1995 to study jazz bass, played in many settings there and was rated a bassist with a good feel, then returned to Korea and joined JS Culture, a mixed-gender new age duo, before leaving for the United States and settling in New York. His label's biography on Bugs adds that he studied at the New School for Jazz and Contemporary Music in New York and finished graduate school at Queens College, City University of New York, where he studied composition, arranging and trombone with Michael Philip Mossman. Yonhap gives the reason for the graduate degree in his own words: his father told him a bassist could not make a living on bass alone and should understand music as a whole, so he studied composition and arranging. At Queens he met a younger trombonist and picked up the instrument at 35. It came easily because, like the bass, it reads in bass clef, and his father also felt that one household did not need two saxophonists.

On August 2, 2004 EBS Space Gonggam presented a concert titled Jazz in New York around him. The listing names Jung on bass with Park Su-yong on alto saxophone, Park Jong-hwa on piano, Hiroyuki Homa on guitar, Tomoaki Kano on drums, Michael Camers on tenor saxophone and Kuroda Takuya on trumpet, and says his father would appear as a guest; the description of the same concert names the pianist Jared Kashkin instead of Park Jong-hwa, so the piano chair is not settled.

Discogs holds two credits for him from the bass years. He plays contrabass on eight tracks of 이성원's children's song album 올해도 과꽃이 피었습니다 (Universal, 2002), a folk record recorded in late summer 2001. And he is the bassist on Nouveau Son (With33Music, 2003), a project that gave Korean pop songs of the 1980s and 1990s jazz arrangements, with Sungjae Son as arranger and saxophonist, Juhan Lee on trumpet and as producer, and the singers Nam Yeji and, credited only by the Hangul name 신예원, a second vocalist. Bugs also lists him on the 2003 JS Culture album Missing. He then recorded Long Ago & Far Away with the guitarist Kim Min-seok, a duo album of standards in which his name is attached to every one of the 13 tracks; Bugs dates it November 15, 2007 on Universal Music Korea, while Melon and Genie list a digital release of August 24, 2009. In 2008 he is credited on the Christmas album Once Upon a December by the duo December (the pianist Park Jong-hoon and Kim Min-seok), on trombone for "Winter Wonderland" and on bass for "Jingle Bell Rock".

Smile (2010, Universal Music Korea) is the bass record. It is billed to the Joonghwa Jung Trio (정중화 트리오), whose pianist and drummer the Bugs page names as Shiina Yutaka and Hirose Junji, and it pairs standards such as Charlie Chaplin's "Smile", Jobim's "Desafinado" and Fats Waller's "Honeysuckle Rose" with three originals; the label text calls it a leader album by a bassist who shows what the bass is for. His label's biography also says he played sessions on pop and jazz records for Brown Eyed Girls and Sunny Hill, and formed JHG (Just Hip'm Groovy), a 12-piece brass band built around his trio with a funk-jazz motto, which played at festivals including Jarasum.

The trombone album came in 2014. Autumn Rain was his first record on the instrument, a collection of nine pieces that Yonhap says he wrote himself, and it was meant as a song of longing for his father. Jung learned in July that his father was gravely ill, and in the interview he says he had wanted to announce the album while his father was alive but could not. The printed dedication reads, in the words Yonhap quotes, that he was giving the album to his father, who was very ill. His father passed away on October 26, 2014, and Korean services list the album from October 27. Jung says two of the pieces had been played with his father at the Itaewon club All That Jazz, where he and his father appeared together every week in the Jung Sung-jo Quintet, and that his father heard a few others in advance and approved. The tribute "Father" he wrote in about five minutes after learning of the illness and never played to him. "Summer Breeze" grew from Gershwin's "Love Walked In", with a bossa nova arrangement his father suggested, and his wife, who studied English literature, named "Nostalgia". The album credits a quintet: Jung on trombone, Han Un-gi on guitar, Ryu Seung-ho on piano and Oh Jong-dae on drums, with his own name also printed against the bass. He told Yonhap he intended to keep releasing trombone albums and to build the SAC Big Band, the student band his father had started at Seoul School of Integrated Arts (서울종합예술학교), where Jung was then a professor in the instrumental department.

Moon Dance followed on December 14, 2016, again on HUKS MUSIC, with Han Un-gi on guitar, Im Mi-jung on piano, Choi Eun-chang on bass and Kim Hong-gi on drums. The critic Hwang Deok-ho is quoted on its Bugs page naming weight, melancholy and swing as the three things about Jung's trombone that cannot be missed, and Jung writes there that he had meant to release an album a year but found it harder than expected, and hopes people listen with morning coffee or an evening glass of wine.

For the fifth anniversary of his father's death he made 아버지 (Father), released on October 15, 2019. He wrote the music and lyrics and produced it; the singers are Son Hye-eun and Lee Jin-hee, with Kim Deok-hwa on piano and strings, Han Un-gi on guitar, Kim Hong-gi on drums, and Jung on bass, trombone and trumpet. In his note he says it was recorded with the Sunday players from All That Jazz and with students from the Seoul Institute of the Arts, and that the title song grew from "Polka Dots and Moonbeams", a tune his father loved. Three of its eight tracks are instrumental piano duets. 애원 (To Be with You, November 13, 2020) reuses several of those songs with a third singer, Yang Ha-eun, and 가을이 오는 소리 (Sounds of Autumn, October 7, 2021), which Bugs lists as a seven-track EP, adds the pianist Im Mi-jung, the guitarist Kim Seong-jun and the alto saxophonist Jo Gyeong-yeong.

In 2022 he guested on two tracks of the pianist Lee Myung-geon's album ST. ART (Mirrorball Music, November 21), including one featuring the singer Malo, and a version of "방앗간집 둘째딸" by him appears on the Bupyeong Cultural Foundation's compilation 부평 사운드 2022 Jazz City Bupyeong. The school chronology for Seoul Institute of the Arts lists a performance by the 정중화 빅밴드 (Joonghwa Jung Big Band) at the Jeonju Jazz Festival under September 2023; a fan video of the set is dated September 15, 2023.

He has said little in print about influences beyond his father, so this section stays with what he and his label wrote. His father's habits shaped him: Yonhap quotes him saying that the older man rose at six every morning to study arranging at the computer with notation software, and that he kept researching bebop in his doctoral studies until his illness. Jung's own training took the same route, from bass into composition and arranging and then into a brass instrument.

The trombone albums are slow, lyrical and melancholy, which the label calls sentimental jazz in a style that suits Korean taste; Yonhap describes the title track as opening with a low, singing trombone line, "Father" as a bright, warm piece led by clear piano rather than sorrow, and "Nostalgia" as notable for the fullness of tone in its melody. Moon Dance is filed by Bugs under standard jazz, 애원 under vocal jazz and 가을이 오는 소리 under contemporary jazz. Apple Music files his four trombone albums under New Age, a tag that comes from the distributor and not from the Korean services, and his early bass work with the duo JS Culture was also new age. The bass-led Smile is a straight-ahead standards trio record. He has written that "넌 사랑" from the 아버지 album was deliberately made accessible, for listeners who think jazz is difficult or noisy.