He has received praise for his work in a wide range of genres, most notably Joint Security Area (2000); All In (2003); A Bittersweet Life (2005); The Good, the Bad, the Weird (2008); I Saw the Devil (2010); Masquerade (2012); and the television series Iris (2009) and Mr. Sunshine (2018).

Lee has seven films—Joint Security Area, The Good, the Bad, the Weird, Masquerade, Inside Men, Master, Ashfall and The Man Standing Next—on the list of the highest-grossing films in South Korea.

[4] Lee and Ahn Sung-ki were the first South Korean actors to imprint their hand and foot prints on the forecourt of Grauman's Chinese Theatre in Hollywood, Los Angeles.

Lee's career began in 1991 after a KBS talent audition and making his debut in the television drama Asphalt My Hometown.

[5] Lee drew attention with the action drama Asphalt Man and romantic film The Harmonium in My Memory,[6] but it was only in 2000 that he made his big breakthrough with Park Chan-wook's Joint Security Area.

In 2001, Lee's popularity continued to climb when he starred in melodramas Beautiful Days and Bungee Jumping of Their Own.

Lee reunited with director Kim Jee-woon in the "kimchi western" The Good, the Bad, the Weird, taking on his first villain role.

[20] Lee returned to television in late 2009 in the espionage action thriller Iris as a secret agent who finds himself at the center of an international conspiracy.

[25][26] In 2010, Lee starred in I Saw the Devil with Choi Min-sik,[27] his third collaboration with Kim Jee-woon, which premiered at the Sundance Film Festival.

[32][33] On June 23, 2012, Lee, along with Ahn Sung-ki, became the first Korean actors to leave their hand and foot prints on the forecourt of Grauman's Chinese Theatre in Hollywood, Los Angeles.

[39] He received praise for his "scene-stealing" role as a young and ambitious warrior with a lowly status, but the film failed to do well and was criticized for its plot.

[41][42] He then starred in Woo Min-ho's political crime thriller Inside Men,[43] which became the top grossing R-rated movie of all-time at the Korean Box Office.

[49][50] The same year, Lee co-starred as knife-wielding gunslinger Billy Rocks in The Magnificent Seven with Denzel Washington, Chris Pratt, and Ethan Hawke.

[51][52] Returning to Korea, Lee starred in the crime thriller Master,[53][54] followed by mystery drama Single Rider.

[61][62] In 2018, Lee made his television comeback in Mr. Sunshine, a historical war drama written by Kim Eun-sook.

[63] The series was a commercial and critical success, and Lee won the Grand Prize at the 6th APAN Star Awards.

[74] On September 14, 2023, Lee was one of the guest speakers chosen to introduce rock star Yoshiki at his imprint ceremony at the TCL Chinese Theatre.

[81] In March 2011, Lee donated 700 million won to the Korean Red Cross to help local residents affected by the earthquake and tsunami in Japan.

[85] In October 2020, Lee made voice donation to multi-media type Braille sensory book by The National Research Institute of Cultural Heritage.

[98] On December 9, 2009, Lee's ex-girlfriend Kwon Mi-yeon filed a civil lawsuit alleging she was tricked into having a sexual relationship with the star based on the promise of marriage.

Lee's agency, BH Entertainment, countered that her claims were all false and that the lawsuit was retaliatory in nature due to the breakup.

He was accused of bringing in gangsters and causing a disturbance due to a conflict with a producer that he claimed spread rumors that Kang was behind the feud between Lee and Kwon.

[113] It was later revealed that the crime was fully intentional and pre-planned, as both Dahee and Lee Ji-yeon looked for plane tickets to escape to Europe[114] and purchased two suitcases to be used for transporting the money.

[123] In March, both women, who were in jail for six months, received a suspended sentence for two years, following Lee's pardon request.