[5] Although considered to have started too late by some, his enormous talent was evident and his reputation grew among the Seoul youth football development community.

In 2003, FC Seoul, then known as Anyang LG Cheetahs in its modern incarnation, then manager Cho Kwang-rae began focusing on developing a youth academy within the team.

FC Seoul at the time signed a handful of youngsters this way, with the most prominent ones being Lee Chung-yong himself, Ko Yo-han, Koh Myong-jin and Song Jin-hyung.

For the next several years, Lee honed his skills in the FC Seoul reserves alongside close friend and international teammate Ki Sung-yueng.

[7] In 2007, Şenol Güneş, famous for coaching the third-placed Turkey national squad in the 2002 FIFA World Cup, joined FC Seoul as manager.

After watching the youngsters Koh Myong-jin, Ki Sung-yueng and Lee Chung-yong carefully, he recognized the players' significant abilities and aimed to use them as important elements in the FC Seoul first team.

FC Seoul confirmed that Lee Chung-yong had agreed a deal to join Premier League side Bolton Wanderers.

[8] The transfer was officially confirmed on 14 August 2009, Lee was reported as stating "I am looking forward to this new chapter in my career and cannot wait to play my first game for my new club.

His good form in his first season continued weeks later, after the international break, as he assisted Ivan Klasnic's first goal in the 3–3 draw against Manchester City at the Reebok Stadium.

He was consequently named 'Man of the Match' by Sky Sports for his significant attacking presence and dribbling prowess: "The South Korean was a constant thorn in City's side and looks to be a real find for Gary Megson.

There was interest from Liverpool after the 2010 FIFA World Cup, but Lee stated that it was likely that he would remain at Bolton for the 2010–11 Premier League,[12] and on 25 November he signed an extension to his contract, keeping him at the club until 2013.

It was initially reported that the injury would rule Lee out for a minimum of nine months,[14] but by early September, Bolton were hopeful that the player would return before the end of the season.

On 2 February 2015, transfer deadline day, Lee signed for Premier League side Crystal Palace for an undisclosed fee with Barry Bannan going the other way on loan.

He has played as a starting player much less frequently, but he has recently led his team to three consecutive league wins by coming in as a substitute and showing himself as a playmaker.

[29] Despite impressing against quality opposition including the United States, Brazil, and Poland, South Korea failed to make the cut for the next round.

On 31 May 2008, Lee was given his national team debut by manager Huh Jung-moo in the 2010 FIFA World Cup qualification match against Jordan.

Lee Chung-yong was one of the most consistent and important players in South Korea's successful seventh consecutive qualification for the FIFA World Cup and eighth overall, an Asian record.

In the last minutes of the game against Belgium, he made a late challenge on Anthony Vanden Borre, ruling the Belgian out for injury for the rest of the tournament as a result.