Kim Hee-chul was born in Hoengseong County, Gangwon Province, on July 10, 1983. He has one older Sister, Kim Hee-jin. Kim graduated from Sangji University with a bachelor's degree in informatics through Bachelor's Degree Examination for Self-Education.
In October 2002, he moved to Seoul in order to take part in the auditions held by S.M. Entertainment. he was cast in the "Starlight Casting System" and signed a contract with S.M. Entertainment and became an official trainee, being trained in areas of singing, acting, dancing, and other performing talents such as hosting and modeling. He was initially placed in a four-member group called "Four Seasons" along with Jaejoong, Yunho and Kangin. The project group was dropped when Yunho and Jaejoong joined TVXQ in early 2003. He was preparing to debut as the main vocalist of Trax, but during his trainee days he had frequent clashes and misunderstandings with the person in charge at S.M. at that time. Therefore, he became frustrated and abandoned his Trax debut and returned to his hometown in Gangwon Province. Later with Trax's Jungmo and Jay, TVXQ's Yunho and Donghae encouragement and positivity, he returned to S.M. He joined other trainees under S.M. Entertainment to form the group "Super Junior 05", the first generation of Super Junior.
His first acting role was in teen drama "Sharp 2 (Season 2)", co-starring labelmates Go Ara and Kibum on 2005 before the debut of Super Junior. Shortly afterwards, he appeared in an episode of the series "Loveholic" and was a regular MC for the cable music show "Show! Music Bank Tank". He also appeared in advertisements.
On November 2, 2005, "Super Junior 05" made their official debut as a twelve-member group on SBS's "Popular Songs", performing their first single "TWINS". Their debut album "SuperJunior05 (Twins)" was released on December 5 and debuted at number three on the monthly MIAK K-pop album charts.
In March 2006, S.M. Entertainment began to recruit new members for the next Super Junior generation. However, plans changed and the company declared a halt in forming future Super Junior generations. Following the addition of thirteenth member Kyuhyun, the group dropped the suffix "05" and became officially credited as Super Junior. The re-polished group's first CD single "U" was released on June 7, 2006, which was their most successful single until the release of "Sorry, Sorry" in March 2009.
Apart from Super Junior's activities, Heechul has acted in several television dramas. In 2005 he landed his first leading role in "Rainbow Romance" (2005–06) then played a supporting role in "Bad Family" (2006), "Golden Bride" (2007–08) and "Loving You a Thousand Times" (2009–10). He also appeared as a radio DJ on "SBS Power FM Youngstreet" with Park Hee-von until mid-2006.
On February 23, 2007, he debuted as part of Super Junior sub-group, Super Junior-T, performing trot single "Rokuko!!!". and made his film debut in "Attack on the Pin-Up Boys". He co-hosted SBS's weekly live music show as a substitute for Andy of Shinhwa, going on to become a permanent host with Ku Hye-sun (April 23, 2006 – February 18, 2007), Jang Keun-suk (February25 - October 7, 2007) and Song Ji-hyo (November 11, 2007 – May 4, 2008).
In May 2008, the S.M. Art Company was formed with Pyo In-bong as co-CEO, aiming to produce musical and theatre works. Its first production was of "Xanadu", playing the role of Sonny in rotation with bandmate Kangin. The production ran between September 9 - November 23, 2008 at the Doosan Art Center, Yeonji-dong, Seoul. Casting was carried out via a reality television programme, "To Be Kangin and Heechul." He also became a regular on the TV Programmes "8 vs 1" (2008), "Good Daddy" (2008–09) and "Band of Brothers" (2009).
In November 6, 2009, he released his first solo single, "First Star", as part of the OST for the drama "Loving You a Thousand Times". The song is written by Song Jong-ho and composed by Choi Myung-hoon.
In 2010, he returned as a radio DJ for the first time in four years on SBS's "Heechul's Young Street" from March 29, 2010 until mid-2011. In May 2010, he was added along with Jang Dong-min during a recording as the eighth member of the family on the series "Family Outing 2", but the show was cancelled two months later due to low ratings. The same year, his popularity skyrocketed when he became a regular cast member in "Radio Star", the main segment of MBC's "Golden Fishery" when Shin Jung-hwan was caught gambling. and won "Best Newcomer Award" awards at the 11th MBC Entertainment Awards.
In 2011, he formed a project group with label mate Jungmo of TRAX called M&D (meaning "Midnight and Dawn" or "Miari and Dangae-dong", after the members' hometowns). They released their debut single, "Close Ur Mouth". Heechul wrote the lyrics and directed the music video for the song, while Jungmo produced and performed the instrumental. Their first live performance was at Mnet’s summer awards ceremony 20’s Choice on July 7.
Kim Hee-chul carried out mandatory military service from September 1, 2011 to August 30, 2013. He served as a public service worker for 23 months after undergoing four weeks of basic training at the Nonsan military camp in Chungcheongnam-do. At the time that he enlisted, he had been appearing on KBS's "Secret" (시크릿) as well as the "Radio Star", for which bandmate Kyuhyun took over the role.
Shortly after he had completed his military service, he featured on Kim Jang-hoon's single "Breakups are So Like Me". During live performances of the song on "Music Bank" and "Show! Music Core", his part was performed by bandmates Yesung, Eunhyuk and Shindong. Also he wrote the lyrics of Orange Caramel's "Shanghai Romance" on October 13, 2011, which peaked at number eight on the Gaon Digital Chart.
On January 26, 2012, he hosted the radio program every Friday at the office of District Seong Dong, where he was serving his two-year mandatory military service. His first episode was broadcast on January 20 and had received 5,600 hits.
In September 2013, he became a regular cast member on the JTBC's variety program "Ssulzun (War of Words)" it was his first project after releasing from his mandatory military enlistment but on July 2014 he posted a photo in his personal Instagram account and poured his heart and thoughts regarding his last appearance in the program. In Heechul’s last recording for the show, he mentioned about having the pressure of talking about the people close to him.
In January 2014, he appeared on the "Global Edition" of MBC reality television programme "We Got Married", as an on-screen couple with Taiwanese girl group member Puff Guo. That year, he also played the role of a detective in the tvN drama "Flower Grandpa Investigation Unit". He returned to the Super Junior's line-up for the August performance at "Music Bank", marking the first time he, Leeteuk and Kangin have been together in the line-up since they each completed their military service.
In February 2015, the famous LoL team SK Telecom T1 sponsored a special match titled the "Celebrity League of Legends Invitational Event Match". SKT T-LoL invited various celebrities to join in a match against professional LoL gamers. The celebrity team including Heechul ultimately lost. He also appeared on OnGameNet’s "Pandora TV LoL Champions" on November 27, 2013 as a Special Commentator and Guest player.
In 2015, he became MC on entertainment programs such as Tvn's "The Demand of Luxurious Food", KBS's Fashion-beauty Show "A Style For You", O'live's Travel Show "MAPS", JTBC's variety show "Knowing Bros". and Korean-Chinese program "All the Way With You", The first Chinese variety that he was in charge since his debut in Korean entertainment in 2005. The same year, M&D released their first EP, "Cottage Industry" with the title track "I Wish" digitally on April 16 and physically on April 20. The title track was also written and composed by the duo., which peaked at number two on the Gaon album Chart.