At the age of ten, he moved to Los Angeles, California, United States where he attended Santa Monica High School.

Kim signed a contract with SM Entertainment and became an official trainee, being trained in areas of singing, acting, dancing, and other performing talents such as hosting and modeling.

Although he resided in Seoul at the time, he constantly returned to Los Angeles to visit his family and to attend short school sessions.

Kim debut as part of 12-member rotational project group Super Junior 05 on November 6, 2005 on SBS's music programme Popular Songs, performing their first single, "TWINS (Knock Out)".

[5] He appeared in Attack on the Pin-Up Boys, a 2007 high school Korean film that starred all members of Super Junior except Kyuhyun.

[6] In April 2008, Kim returned to acting after 16 months, starring in another daily MBC drama, Chunja's Happy Events alongside Wang Bitna.

SM finally issued a statement stating that Kim was busy with solo projects, and re-confirmed he would be absent from promotional activities, but that he had not left Super Junior.

[8] In May 2010 it was confirmed that Kim would neither participate in the fourth album, Bonamana, nor any further Super Junior activities until further notice, as he would be focusing on his acting career.

[9] In October 2011 Kim played Joseon scholar-official Pak Paengnyeon in historical drama Deep Rooted Tree.

On January 13, 2022, it confirmed that Kibum left from Clover Company and signed an exclusive contract with PA Entertainment and plans to accelerate his acting activities in the future, starting with fan meetings in March 2022.