Kim Jung Hyun is a South Korean actor under managementSEESUN (매니지먼트 시선). He was born in Busan, South Korea. He majored in acting at the Korea National University of Arts and completed his mandatory military service at twenty-one years old.

After getting his start in musical theatre, Jung Hyun made his silver screen debut in 2015 with the film "Overman" (초인). He made his television debut in the series "Jealousy Incarnate" (질투의 화신). He then starred in the drama "Rebel: Thief Who Stole the People" (역적: 백성을 훔친 도적), for which he won the Best New Actor award at the 2017 MBC Drama Awards. In 2018, amidst the controversy with Seo Yea Ji, which resulted in his actions and behaviour affecting his co-star Seohyun and the filming, he withdrew halfway through the run of the drama "Time" (시간). While playing a terminal patient with a few months to live, he was unable to continue due to an "eating disorder and sleep disorder." He had previously been diagnosed with anxiety disorder, panic disorder, sleep disorder, and had depressive episodes. He returned to television in December 2019 when he joined the drama “Crash Landing on You” (사랑의 불시착), which became the highest-rated tvN drama and the third-highest-rated Korean drama in cable television history. He left O& Entertainment after his contract expired and signed with Story J Company in September 2021. On January 6, 2025, Story J Company announced that his exclusive contract would end in February and that he had decided not to renew the contract.