[7] In a profile of his father when Lee Jung-hoo was seven years old, he was already attracting attention for his devotion to baseball and his skill at the game.

Following spring training, Lee was included on the team's Opening Day roster at age 18 without going through the KBO Futures League.

His father, Lee Jong-beom, won the MVP award in the 1993 Korean Series, with a batting average of .310 (9 hits in 29 at-bats) and three steals, the most in a game.

[9] Lee won another Golden Glove Award in 2020[10] with a batting line of .333, 15 home runs, 101 RBIs, and a career-high OPS of .921.

[13] On December 14, 2023, Lee signed a six-year, $113 million contract with the San Francisco Giants of Major League Baseball.

Lee’s first appearance in the international stage was at the 2016 U-18 Baseball World Cup, as South Korea won the tournament.

Lee then went onto represent the national team in the 2017 Asia Professional Baseball Championship, where South Korea place 2nd overall.