Conley, 33, is averaging 16.1 points, 5.7 assists and 3.5 rebounds in 29 games this season as he continues to bounce back from a dismal 2019-20 campaign. The Jazz now have three players in the All-Star Game with Conley joining Donovan Mitchell and Rudy Gobert.
Booker, who is averaging 24.9 points, 4.4 assists and 3.6 rebounds per game, was selected as a reserve by Team Durant during Wednesday's All-Star Draft. The Phoenix star is being held out with a left knee sprain, according to the NBA's announcement.
Commissioner Adam Silver chose Conley as Booker's replacement with rules stipulating a substitute must be selected from the same conference as the injured player.
Conley will also replace Booker in the three-point contest ahead of Sunday's exhibition.
It's the first All-Star Game appearance for the 14-year veteran who immediately received congratulations on social media from Gobert and Mitchell.
Now a member of Team Durant, Conley will reunite in the backcourt with Mitchell as the duo look to help end LeBron James' streak of three straight All-Star Game victories.