PSG has now secured the season-opening cup on 14 different times.
The Parisian giants required a dramatic equaliser followed by a successful spot-kick decider to get past their arch-rivals in the Gulf and secure a fourth straight Trophee des Champions victory.
The European champions appeared to be sailing towards a straightforward triumph in the match featuring the French league winners and the French Cup holders after Ousmane Dembele opened the scoring in the opening stages.
Yet, the southern French side struck twice in the closing moments to seize a shock lead. First, the English forward scored from the spot-kick, before Willian Pacho inadvertently turned the ball into his own net for an own goal.
In a remarkable twist of events, Goncalo Ramos grabbed a vital equaliser in the final seconds to force the match into a penalty shootout. PSG goalkeeper Lucas Chevalier then stood as the hero, saving crucial attempts from O'Riley and Hamed Traore.
From the spot, Goncalo Ramos, Vitinha, Nuno Mendes, and Desire Doue all converted with composure for PSG to complete a 4-1 penalty victory.
The record winners PSG, who faced last season's Ligue 1 runners-up Olympique de Marseille after achieving a league and cup double, have now won this trophy for the twelfth time in the past 13 years.
