Kylian Mbappe era by lifting the Champions League trophy at Wembley in June.
Their hopes of going all the way in Europe's elite club competition for the first time hung in the balance after they lost 3-2 at home to Barca in the first leg of their quarter-final last week.
They had never previously won a Champions League knockout tie after losing the first leg at home, and their prospects of doing so this time appeared slim after they conceded the opening goal on the night.
Another disappointing exit threatened for the Qatar-owned club who had gone out in the last 16 in five of the previous seven seasons.
But they seized the opportunity given to them in Catalonia after Ronald Araujo's red card left Barcelona to play over an hour with 10 men, allowing Luis Enrique's team to go on and win 4-1 on the night and 6-4 on aggregate.
PSG were rampant with the extra player, as Ousmane Dembele again stood out against his old team by scoring the equaliser on the night and winning a penalty which Kylian Mbappe converted to put PSG ahead in the tie.
In between, the outstanding Vitinha — who had already scored in the first leg — netted with a brilliant strike from outside the box, and Mbappe made sure of the win late on to spark wild celebrations in the away contingent at Montjuic.
«It is a magnificent, historic moment for the club. It is not easy to win here, but I was confident. I told the coach we were going to win and qualify,» PSG president Nasser al-Khelaifi proudly told broadcaster Canal Plus.
The final scoreline was