Soyoung Heo (허소영) is a South Korean jazz vocalist who has built her reputation on American standards sung over small, drummer-free ensembles. She has made three albums under her own name, Her, So Young & Old (2009), That's All (2013) and B.B.B. (2018), plus the EP Celebrate in Paradise (2020). That's All was one of six albums nominated for Best Jazz & Crossover Jazz Album at the 11th Korean Music Awards in 2014. Her name appears in Latin letters in several forms: Soyoung Heo on the Discogs credits for her releases and in Korean Wikipedia, Heo Soyoung on Apple Music and Wikimedia Commons, Hur So-Young on MusicBrainz, and Heo So-young in some Korean press and credit lists. They all refer to the same singer.

Korean Wikipedia and Wikidata give her birth date as January 29, 1984, and Korean Wikipedia files her among the natives of Cheongju. The same article says she entered Baekje Arts University in 2002 and Yewon Arts University in 2007. In an interview on Melon she said she had sung since childhood and met jazz seriously at Baekje, where the curriculum centered on it and visiting jazz players performed; she said she did not love the music at first and grew into it through her classes and her teachers there. Korean Wikipedia dates her debut to 2006 and lists her with the group HourmeltS (아워멜츠), whose releases it gives as Twenties = Love (November 1, 2007) and Meaningful Days (May 8, 2009). In the Melon interview she described her part in that electronic band's first album and EP as indirect, and said she had also sung as a guest with the hard bop band Portrait (포트레이트) and on the fifth album of the band Prelude (프렐류드), 5th Movement (November 12, 2010), whose release text names her as its vocalist.

Her first record under her own name was Her, So Young & Old, which Korean Wikipedia dates to February 26, 2009. The Melon interview says her career began in earnest with it, and Korean Wikipedia describes it as an album with Korean-language lyrics that marked her out as a notable newcomer. A 2013 review on the dental-industry news site Dentin says its songs were originals dedicated to jazz masters. Little else about that release is documented online.

Four years later came That's All. Its first single, "Destination Moon," came out on February 15, 2013, and the album followed on February 28. A Dentin piece from March 2013 describes a record of standards reinterpreted, performed by an unusual trio of piano, double bass and guitar with no drummer, and singles out a piano version of "Destination Moon." Korean Wikipedia credits the album with establishing her among Korea's capable jazz singers and mentions her command of scat singing. On February 4, 2014, the Xportsnews site listed the six nominees for Best Jazz & Crossover Jazz Album at the 11th Korean Music Awards: Kim Oki's Cherubim's Wrath, the Kim Ji-hoon Trio's Preeminent, Nah Youn-sun's Lento, Park Sung-yeon's Park Sung Yeon with Strings, the Yun Seok Cheol Trio's Love Is a Song and Heo's That's All. Tenasia's report of the February 28, 2014 ceremony shows that Lento took the prize. Around the album she played Seoul's Evans Day series (a 2013 summer edition was held August 23 to 25 at Muse Live Hall in Olympic Park, according to Kyunghyang Weekly) and appeared on the EBS Space Gonggam television series, which Korean Wikipedia lists as episode 937 on June 20, 2013 and episode 1051 on August 21, 2014.

After that the recorded trail thins. The Bugs listing shows her on the soundtrack of the 2015 television drama 유일랍미 (released November 30, 2015), and no release under her own name until the end of 2018. On November 28, 2018 she released B.B.B., her third album, with a limited vinyl edition that Insight reported had been previewed at the 8th Seoul Record Fair and sold out within two hours. Discogs dates the limited LP to November 10, 2018 (MDNT, MD708L). It has eight standards: "Baubles, Bangles and Beads," "I've Got a Crush on You," "It Might as Well Be Spring," "Two Sleepy People," "Blue Room," "Dream Dancing," "Only Trust Your Heart" and "I Get Along Without You Very Well." Discogs credits Paul Kirby on piano, Joon Smith on guitar and Jinkyo Park (박진교) on bass, with arrangements by Park and Heo, executive production by Kang Woong (강웅) and photography by 신새벽. The Insight article, published November 29, 2018, repeats the nickname that followed That's All, "Korea's Sarah Vaughan," and says the album follows the style of her best-known songs, "Destination Moon" and "That's All." It announced a release concert for December 9 at Mood Lab in Seongdong-gu, Seoul. The jazz critic Hwang Deok-ho, who hosts the KBS Classic FM program Jazz Notebook, called her one of Korea's representative jazz vocalists in his recommendation for the album, according to Korean Wikipedia.

The next years brought guest work and a smaller record. She is the vocalist on "두무개길," a track on the 2019 EP 여, 행하라, credited to 전수경, which Korean Wikipedia describes as a collaboration between the announcer Yoon Young-mi and the director Jeon Su-kyeong on a theme of travel through Korea's scenic places (September 26, 2019). Korean Wikipedia lists a joint EBS Space Gonggam episode with the vocalist Stella Jang (episode 1430, May 23, 2019), and the Kyeonggi Ilbo named her among the domestic acts at the 16th Jarasum Jazz Festival, held October 4 to 6, 2019. The single "잘자요" followed on March 9, 2020 and the four-track EP Celebrate in Paradise on June 22, 2020. Its personnel, per Discogs, are 곽정민 on piano, 신동하 on bass and 김민찬 on drums, who also arranged, with Heo on vocals, production and arrangement. The Jarasum Jazz Festival's YouTube channel carries a 2020 performance of the title song by the Heo So Young Trio, and the EBS Space Gonggam channel a pre-release video of it. A 2025 EP, WINTER, credited to 전수경, carries her name in the Bugs listing. Her management is listed in Korean Wikipedia as So Young Music, and no source gives where she is based now.

Her identity is repertoire and tone: standards from the Great American Songbook sung with a swinging, warm delivery, usually over piano, guitar and bass. In the Melon interview she named Sarah Vaughan, Dianne Reeves, Nancy Wilson, Billie Holiday, Abbey Lincoln, Stacey Kent and Nah Youn-sun as favorite vocalists, adding that some have a voice color close to her own. Reviews and Korean Wikipedia stress her swing feel and her scat. Her debut was different, built on original songs with Korean lyrics, and her 2019 and 2020 pieces return to Korean-language material.

Her record is jazz from the start; the guest, soundtrack and travel-project credits are a small part of it, and no pop or other genre identity competes with her jazz one.