PSG has now won the season-opening cup on 14 different times.
The Parisian giants required a stoppage-time equaliser followed by a successful penalty shootout to overcome Marseille in the Gulf and secure a fourth straight Trophee des Champions victory.
The Champions League holders seemed to be coasting towards a comfortable win in the showdown between the French league champions and the Coupe de France winners after Ousmane Dembele opened the scoring in the opening stages.
However, the southern French side fired two times in the closing moments to seize a shock advantage. First, Mason Greenwood scored from the penalty spot, before Willian Pacho inadvertently turned the ball into his own net for an own goal.
In a remarkable twist of fortune, the Portuguese striker snatched a crucial equaliser in the final moments to send the contest into a deciding shootout. The Parisian shot-stopper Lucas Chevalier then emerged as the hero, stopping crucial attempts from O'Riley and Hamed Traore.
In the shootout, Ramos, Vitinha, Nuno Mendes, and Desire Doue all scored successfully for Paris Saint-Germain to complete a convincing shootout victory.
The record champions PSG, who faced last season's Ligue 1 second-placed team Olympique de Marseille after achieving a domestic double, have now won this trophy for the 12th time in the last 13 seasons.
