Lee is considered one of the best defensive third basemen in the KBO league. He is also able to make great contributions on offense as well. He hits with considerable power, which has enabled him to collect 20+ home runs every season.
Lee made his pro debut in 2000, drafted by the Hanwha Eagles in the 2nd round (8th pick, 16th overall) of the 2000 KBO Draft.
He had a couple of mediocre seasons as a backup shortstop, but started to show signs of promise in 2002 when he batted .260 and hit 11 home runs. After the 2002 season, Lee was selected for the South Korea national baseball team for the first time and competed in the 2002 Intercontinental Cup held in Cuba. In the Gold Medal game, Lee hit a solo home run off Cuba's starter José Ibar in the bottom of the 4th inning to break a 0-0 tie.
His stats dipped slightly in 2003, but broke out again in the 2004 season when he batted a career-high .308 with 23 home runs and 74 RBIs, playing in all 126 regular-season games as a shortstop.
In 2005, Lee moved from shortstop to third base, and hit a career-high 26 home runs with 68 RBIs. He won his first Golden Glove award at third base, edging out Kim Dong-Joo in the balloting.
From 2004 through 2007, Lee had four consecutive seasons with 20 or more home runs.
In 2008, he batted .276, hit 19 home runs, drove in 77 runs and stole a career-high 12 bases.
In March 2009, Lee competed for the South Korea national baseball team for the 2009 World Baseball Classic. For the Classic, Lee went 8-for-20 with 3 home runs, 5 runs and 7 RBIs in six games. He was fifth in RBI and tied for the lead with six others in home runs in the tournament, and named to the All-Star team at third base. In the 2009 KBO season, Lee had another solid performance, batting .284 with 25 home runs (7th in the league), 124 hits and a career-high 79 RBIs in 126 regular-season games as a third baseman.
Lee signed as a free agent with the Fukuoka Softbank Hawks of the Japanese Pacific League in November 2009. He batted .226 in 48 games for the Hawks in 2010, with 4 home runs and 8 RBI. He hit his first NPB home run on 4/9/2010 against Nippon Ham at Fukuoka Dome in the seventh inning off Hirotoshi Masui.