Weverton denied the Mexicans an opener from a header off from a cross three minutes in, as Palmeiras received a rude awakening fresh from the start of proceedings in Qatar.
The South American champions soon staved off the nervy start and began to pose all the danger much of the first half, with Rony and Raphael Veiga the main protagonists in this regard.
Tigres went close to go in front late in the half through the head of Andre-Pierre Gignac, but the Frenchman directed his attempt wide from a cross by Luis Rodriguez.
Palmeiras were behind nine minutes in the second half when Gignac fired home from the spot after a foul in the area on Carlos Gonzalez.
The Brazilian side attempted level matters late on, but the Mexican side did enough to secure the win and a spot in the final of the Club World.
Tigres will now await the winner of Monday's semi-fina between Bayern Munich and Pitso Mosimane's Al Ahly.