The side won 87-79 today against the Boston Celtics in game seven of the Eastern Conference finals.
James has reached the NBA Finals in eight straight seasons, including four in a row with Cleveland. Only Bill Russell (10), Tom Heinsohn (9) and Sam Jones (9) have made more consecutive appearances in NBA history.
The Cavaliers will play tomorrow's game 7 winner of the West finals series between Houston and Golden State. Cleveland has faced the Warriors in the last three NBA Finals, winning in 2016 and losing in 2015 and 2017.
Jayson Tatum scored 24 points to lead the Celtics, who lost at home for the first time this postseason in 11 games. Al Horford added 17 points and Marcus Morris had a double-double with 14 points and 12 boards.
Boston was denied its first Finals trip since 2010, when it lost to the rival Los Angeles Lakers in seven games.
Jeff Green had 19 points and eight rebounds, JR Smith scored 12 points and Tristan Thompson had 10 with nine boards for the Cavaliers.
Cleveland won without former All-Star forward Kevin Love, who missed the game after sustaining a concussion in Game 6. Love has entered the NBA's concussion protocol and his status is uncertain.
James, who entered with an NBA-record Game seven average of 34.9 points, improved to 6-2 lifetime in Game sevens.
Green's three-pointer with 4:56 left in the third quarter gave Cleveland its first lead since the opening minutes at 53-51. The Cavs went ahead by as many as five after that before taking a 59-56 lead into the fourth.
Tatum hit a three after his driving dunk over James put Boston up 72-71 with 6:04 remaining in the game, but Green answered with another 3 at the 5:44 mark and Cleveland didn't relinquish the lead after that.
Boston was up 43-39 at halftime after leading by as many as 12 in the first half.
James went flying into the stands with less than nine minutes left in the first quarter trying to deflect a full-court pass out of bounds. After slowly getting back on his feet, James shook hands with a fan he knocked over.
Boston led 26-18 after one quarter.
