When Leeteuk and his older sister, Park In-young, traveled to Myeongdong for a holiday in early 2000, he was recommended by a talent scout to audition for SM Entertainment's Starlight Casting System
, an audition that selects artists to sign under their label. After several test recordings and performances, he signed into SM Entertainment and became the company's trainee. That same year, he had his first quick television appearance as an extra in the MBC Korean drama All About Eve
, and appeared as a brief model for Pepsi in 2002. In 2003, Leeteuk was put into a five-member boyband with future bandmate Donghae, but the project was quickly dropped. They were then put into the large rotational group Super Junior along with ten other boys. Older than the other trainees, Leeteuk became the leader of the group.
On November 6, 2005, Leeteuk officially debuted on SBS's Popular Songs
music program as a member of Super Junior 05
, the first generation of Super Junior. The group performed their first single "TWINS (Knock Out)" to an audience of about 500 fans. Leeteuk explained that he uses a stage name due to his desire to have a name with the same effects as Kangta (and to also prevent confusion with veteran actress Park Jung-su). His stage name denotes being "special" as he wants to be a special member in the group. Leeteuk also became known as the "special leader" (특별한리더) of the group.
Around March 2006, SM Entertainment began to recruit new members for the next generation of Super Junior, and Leeteuk would still remain as the leader of Super Junior 06. However, plans changed when the company added a thirteenth member to the group, Kyuhyun, and declared a halt in forming future Super Junior generations. The group dropped the suffix "05" and became officially credited as Super Junior. The re-polished group hit big after they released their first CD single "U" the following summer, which became Super Junior's most successful single in the music charts until the release of "Sorry, Sorry" in March 2009.
During his career with Super Junior, Leeteuk was put into two subgroups, smaller groups that are branched off of the larger Super Junior group. In February 2007, Leeteuk was placed in the trot-singing Super Junior-T. A year later, Leeteuk became a member of Super Junior-Happy. On April 19, 2007, almost two months after Super Junior-T's release of their first single "Rokuko", Leeteuk became seriously injured in a car accident when returning home after a recording of the radio show Super Junior Kiss the Radio
. Along with Leeteuk, Shindong, Eunhyuk, Kyuhyun, and two managers were also victims. While Shindong and Eunhyuk suffered minor injuries, Leeteuk and Kyuhyun sustained more serious injuries, which required for both to be hospitalised for several more weeks. Leeteuk had glass shards embedded into his back and above his eyes, requiring over 170 stitches in removing most of them. Leeteuk was discharged from the hospital on April 30, 2007. Due to this injury, Leeteuk's role in Super Junior's first big-screen production, Attack on the Pin-Up Boys
(2007) was cancelled. However, it was revealed at the end of the film that he'd taken on the role as the panda mascot, which was later confirmed that it had actually been Ryeowook who'd portrayed the panda in most of the film.
See Super Junior
2007 - Attack of the Pin Up Boys
2000 - All About Eve