PSV Eindhoven Nguyen began his professional career by signing a three-and-a-half-year deal with Dutch
Eredivisie team
PSV Eindhoven in February 2006, but after making just two appearances with the club's senior team, he moved on to get more first-team time somewhere else.
Randers FC On January 31, 2008, Nguyen signed with the
Danish Superliga club
Randers FC until the summer of 2009. He made 23 appearances with the club in parts of two seasons. Nguyen became the Vietnamese league's first American player when he signed with Hoàng Anh Gia Lai on January 17, 2009. He scored 13 goals and 16 assists in 24 appearances in all competitions for the club in 2009.
Becamex Binh Duong In January 2010, Nguyen signed with another
V.League 1 club,
Becamex Binh Duong F.C. in
Thủ Dầu Một. Injuries limited his impact as he scored just one goal in five appearances for the club in one and a half years. On March 2, 2012, he was selected by the New England Revolution with the second overall pick in the MLS Waiver Draft. Nguyen made 30 regular-season appearances for the Revolution in
2012, including 27 starts. He finished second on the team in scoring with five goals (two assists) and was voted the
Midnight Riders Man of Year by the fans. He was named MLS Player of the Week for matchweek 10 following that performance, and also named Revolution Team Most Valuable Player for 2012. In
2013, Nguyen appeared in 33 league matches, scoring four goals and recording seven assists, helping the Revolution reach the playoffs for the first time since
2009. and again being voted the
Midnight Riders Man of the Year. He was named Revolution Team MVP, MLS Player of the Month for October, a
2014 MLS-All Star, and an
MLS "Best XI" selection. Nguyen's goal against the
Houston Dynamo (which was named MLS Goal of the Week for matchweek 32) also made it to the final round of voting for the 2014 version of the
MLS Goal of the Year Award. He was named MLS Player of the Week for matchweek 32. During the
2016 season, Nguyen became the Revolution's team captain. He led the team in assists, with 10, and finished 3rd in goals scored, with 6. He additionally led the team in matches started, with 33, and minutes played. He would finish the
2017 season first in assists, and second in goals scored, with 15 and 11 respectively. He again led the team in games started (tied with
Andrew Farrell. The dispute would ultimately lead to his sitting-out the team's pre-season training camp.
Los Angeles FC On May 1, 2018, New England traded Nguyen to
Los Angeles FC in exchange for $350,000 in General Allocation Money and $350,000 in Targeted Allocation Money. On July 26, 2018, Nguyen scored on a free kick leading Los Angeles FC to a 2–0 lead over
LA Galaxy. The match ultimately ended 2–2 after a second-half comeback by their crosstown rival.
Inter Miami CF On November 19, 2019, Nguyen was selected by MLS expansion side
Inter Miami CF in the
2019 MLS Expansion Draft.
Return to New England Revolution Nguyen was traded back to the Revolution on September 8, 2020, for a fourth-round selection in the
2021 MLS SuperDraft and up to $50,000 in General Allocation Money. Nguyen made 12 appearances for the Revolution in 2020, starting 8 matches and scoring one goal, an 80th-minute penalty against
NYCFC on October 11.
Ho Chi Minh City FC On December 25, 2020,
Ho Chi Minh City announced the signing of Lee Nguyen. On August 8, 2021, Nguyen left Ho Chi Minh City to return in Texas as the
2021 V.League 1 season ended early due to the
COVID-19 pandemic in Vietnam.
Return to soccer and 2nd stint at Ho Chi Minh City After retiring from playing and becoming the assistant coach of the
Washington Spirit in early 2022, on August 6, 2022, Nguyen came out of retirement and return to play for Ho Chi Minh City.
The Soccer Tournament In 2023, Nguyen played in
The Soccer Tournament with ZALA FFF. ==International career==