Jaehyun

Jaehyun is the leader of the South Korean boy group BOYNEXTDOOR, a six-member act under KOZ Entertainment. Born Myung Jae Hyun on December 4, 2003, in Daebang-dong, Dongjak-gu, Seoul, Jaehyun briefly lived abroad as a child and trained under YG Entertainment before eventually joining KOZ Entertainment, where he impressed producer Zico with his self-produced music. A former soccer team captain in school, Jaehyun carried the same discipline and drive into his idol career, quickly rising to become BOYNEXTDOOR’s leader.

Jaehyun debuted with BOYNEXTDOOR on May 30, 2023, with the single album WHO!, and has since become one of the group’s most musically involved members, holding writing and composing credits on nearly half of BOYNEXTDOOR’s discography, including releases like WHY.., HOW?, 19.99, No Genre, and The Action. Beyond his group activities, Jaehyun expanded his career as a broadcaster, becoming an official MC for “M Countdown” on January 11, 2024, alongside ZEROBASEONE’s Sung Hanbin and RIIZE’s Sohee — a role that showcased his natural charisma and quick wit to an even wider audience.

As leader, Jaehyun is known for putting the group first, carrying real emotional weight behind his cheerful, mood-maker exterior. He has admitted to crying alone after debut, feeling the pressure of new responsibilities, yet he consistently shows up as one of BOYNEXTDOOR’s most energetic and reliable members. A devoted dog lover who calls himself the group’s own “doggy,” Jaehyun enjoys soccer, golf, songwriting, and drawing fashion inspiration from artists like Pharrell Williams and Tyler, the Creator. His warm, approachable personality and creative drive have made him a standout figure both within BOYNEXTDOOR and across the wider K-pop industry.