Kim Hyun-jin (, ; born November 15, 2000), known mononymously as Hyunjin (occasionally stylized as HyunJin) is a South Korean singer. She is a member of Loona, its sub-unit Loona 1/3, and leader of its spinoff Loossemble. She is also the drummer for the band Latency.
Kim Hyun-jin was born on November 15, 2000, in Dunchon-dong, Gangdong District, Seoul, South Korea. She has two older brothers. One brother is a vocalist for the band 'BI-O-NE', and the other is an actor. She graduated from Hansung Girls High School in 2019.
In 2013, when she was thirteen years old, Hyunjin appeared on the 40th episode of Three Idiots, a Korean reality TV show. She was introduced as a natural beauty and demonstrated her skills in skipping rope.
On October 23, 2016, the first "Who's Next Girl?" teaser was posted by BlockBerry Creative, and Hyunjin was fully revealed as the second member of Loona on October 28. She released her debut single album HyunJin with her solo single "Around You" and second track "I'll Be There" featuring first member Heejin on November 17. In December, Hyunjin and Heejin were featured on third Loona member Haseul's debut single album for the song "The Carol".
On January 16, 2017, Hyunjin collaborated again with Heejin on the song "My Sunday", released on fourth Loona member Yeojin's debut single album. On February 14, Hyunjin was revealed to be a member of Loona's first sub-unit Loona 1/3. The group debuted on March 13 with their extended play Love & Live. In October, Hyunjin, alongside fellow Loona members Heejin and Haseul, auditioned for the survival reality show Mix Nine. Hyunjin passed the audition and became a contestant as a representative of BlockBerry Creative and Loona. She made it to the final episode, but was eliminated and did not make the final lineup.
On August 20, 2018, Hyunjin officially debuted with Loona as a full group with the release of their debut extended play [+ +]. On September 27, 2020, Hyunjin appeared on South Korean television program King of Masked Singer as a contestant with the stage name Jade Bead. In November 2022, Hyunjin appeared as a panelist for MBC's 2022 FIFA World Cup Qatar preview show Catharsis until being suddenly absent from the program starting November 27.
On February 3, 2023, Hyunjin and fellow Loona member ViVi filed lawsuits to terminate their contracts with their company BlockBerry Creative. On May 9, Hyunjin and ViVi won their injunctions against BlockBerry Creative and terminated their exclusive contracts. On June 12, Hyunjin and ViVi officially signed with CTDENM, a newly formed company founded by BlockBerry Creative's former planning division director Yoon Doyeon.
On August 2, Hyunjin was revealed as an official member of Loossemble, alongside Loona members ViVi, Go Won, Yeojin, and Hyeju, with Hyunjin as the leader of the group. The group debuted on September 15, with their self-titled extended play.
On November 29, 2024, CTDENM announced that the Loossemble members' exclusive contracts with the label had ended.
On June 14, 2025, Hyunjin announced her first fan meeting to be held at K-Pop Stage in Hongdae, Seoul on June 20, with tickets selling out quickly after opening. That same month, Hyunjin founded her own independent artist label named Triangle ENM. She stated the name came from the vertices of a triangle representing the self, reality, and one's dreams, and that she plans to recruit other artists in the future. Hyunjin also announced that she was joining a band project as the drummer alongside former Cignature member Jeewon with an album planned.
On July 16, 2025, Hyunjin was revealed as a participant in YouTube channel Studio USOG's web variety show Another Day of Debut Training. On August 14, through the show, Hyunjin debuted as a member of TDYA with the single "Keep the Light" composed by singer-songwriter Ejae and written by fellow TDYA member Mirani. On August 15, the group performed the song for the first time at Gwanghwamun Square in Jongno-gu, Seoul in a set of performances celebrating the 80th National Liberation Day of Korea.
On October 15, the web series Motchuh Do Rock! began, following Hyunjin as a drummer forming the band Latency alongside Youtuber Fingerstylish, also known as Heeyeon, and Cignature members Jeewon, Semi, and Haeun. On November 18, Oddinary Records announced Latency would debut in January 2026. Latency debuted on January 8, 2026 with "It Was Love".
All credits are adapted from the Korea Music Copyright Association, unless cited otherwise.