Jonghyun was born on May 15, 1990, in Busan, South Korea. He was born into a middle-class family as the youngest of three kids. His family moved around constantly as a kid, eventually returning to Busan and settling there. Jonghyun regards Japan as his second home since he spent so much time there with his family.
Jonghyun was always a fan of music and often listened to American rock music. He once saw Eric Clapton and decided that the life of a musician was the life he wanted to live. So, he enrolled in guitar classes and learned to play very quickly. During his middle school days, he also entered into martial arts but he knew music was his true passion.
In 2007 Jonghyun auditioned for FNC Entertainment. He passed his audition and met some fellow musicians who would later be his band-mates. He then began his training at the FNC Academy.
By 2009, CNBLUE had been formed and the group traveled to Japan to study music and see what kind of music audiences would like. The group would play live shows on the streets and they gained a good response from the Japanese public. This is when they began working on their debut album. In August of 2009, CNBLUE released their first mini album Now or Never in Japan. It was an English language album and it was received well by the Japanese public.
In January of 2010, they officially debuted in Korea with their first mini album Bluetory with the title track "I'm a Loner". Jonghyun and one of his labelmates Juniel collaborated for the single "Romantic J" in December of 2013.
Later in 2010, Jonghyun and his bandmate, Kang Min Hyuk appeared in the film Acoustic. Jonghyun was revered for his performance in the film and was thought he could do acting full-time. However, he did not want to put music aside, as that was his true passion. After that, he declined many opportunities to star in films, dramas, and variety shows.
However, in 2012 the drama A Gentleman's Dignity caught his attention and he became a part of the cast. Although he did well in the public's eye, he still felt reluctant and insecure. He has said that his strength is in his music, that he does well in music and lacks the confidence to do other things. His CEO even had to push him to audition for A Gentleman's Dignity.
From here on out, Jonghyun started to be in more and more casts. In 2013 and 2014 he starred in Adolescence Melody and One Sunny Day respectively. His popularity was slowly increasing as CNBLUE continued to promote and he was cast in more and more dramas.
In July 2016, Jonghyun debuted in Japan with his first solo album, Sparkling Night and it was a hit in both Japan and South Korea. The album sold more than 13000 copies leading to Jonghyun having his first solo concert.
- "Acoustic OST Part.2" ("High Fly" with Kang Min Hyuk) (2010)
- "A Gentleman's Dignity OST Part.5" ("내 사랑아") (2012)
- Sparkling Night (2016)
- Metropolis (2018)
Producing & songwriting credits
- Welcome to Sparkling Night (2016)
- Acoustic (2010)
- Ikiru Machi (2018)
- A Gentleman's Dignity (SBS, 2012)
- Adolescence Medley (KBS2, 2013)
- One Sunny Day (Line TV, 2014)
- Orange Marmalade (KBS2, 2015)
- My Only Love Song (NAVER TVcast & Netflix, 2017)
- Lingerie Girls' Generation (KBS2, 2017)
- That Man Oh Soo (OCN, 2018)
- We Got Married (MBC, 2015)
- Fluttering India (KBS, 2015)
- King of Mask Singer (MBC, 2017)
- Law of the Jungle (SBS, 2017)
- Jonghyun was a couple with Gong Seung Yeon on the show We Got Married
- Jonghyun had a lot of girlfriends when he was in middle school.
- He owns two dogs and a cat loves them to death.
- Jonghyun once said if he had to add a member of FT Island to the group, he would choose Jaejin.
- He refers to himself as an "ordinary" man (dime a dozen).
- His happiest point of the day is when he can take a shower after performing or a party.
- When he's in a good mood in his free time, he likes to go fishing.
- He loves philosophy and one of his favorites to read is Karl Marx.
- Jonghyun said he wants fans to listen to his songs "From the morning to bed".