Lebanon scored in the 15th minute on a counter attack for a 1-0 lead.
Chase Earls brought the Golden Bears into a tie on a header from a Briscoe Massa free kick.
Senior Chris Pugh’s free kick was turned into the go-ahead goal.
Cole Hunter kept Lebanon out of the net the rest of the way to send Mt. Juliet into an 8 p.m. semifinal Wednesday against Wilson Central, a 2-1 winner over Beech, at Hendersonville’s Drakes Creek Park. The winner will advance to the finals and the Region 5-AAA tournament.