The duo have been joined by Carmelo Anthony, Dwayne Wade, Chris Paul and Chris Bosh in the squad.
Miami Heat star James wrote on Twitter: "It's a honor and privilege to be one of the finalist of Team USA! Wanna thank Jerry Colangelo and Coach K!"
The squad will be reduced to 12 players before the beginning of the games.
Team USA will be defending their Olympic title after winning at the Beijing games in 2008.