PSG has now secured the prestigious trophy on 14 separate times.
The Parisian giants required a stoppage-time equaliser followed by a successful spot-kick decider to overcome their arch-rivals in Kuwait and capture a fourth straight Trophee des Champions victory.
The European champions seemed to be sailing towards a comfortable win in the showdown between the French league champions and the Coupe de France holders after Ousmane Dembele found the net early on.
Yet, Marseille fired two times in the closing moments to seize a surprise advantage. Initially, Mason Greenwood converted from the penalty spot, before the defender inadvertently turned the ball into his own net for an own goal.
In a breathtaking twist of fortune, Goncalo Ramos snatched a crucial leveler in the dying seconds to send the match into a penalty shootout. PSG goalkeeper Lucas Chevalier then stood as the hero, saving crucial attempts from Matt O'Riley and Hamed Traore.
From the spot, Ramos, the midfielder, Nuno Mendes, and the young talent all scored with composure for PSG to complete a convincing shootout win.
Now 14-time winners Paris Saint-Germain, who met last season's Ligue 1 second-placed team Marseille after achieving a domestic double, have now lifted this trophy for the twelfth time in the past 13 seasons.
