But PSG continued to attack at will and Pastore’s assist for Di Maria allowed the winger to grab his second of the game on 59 minutes.
The hosts were gifted another when Falcao’s attempt to clear a corner went horribly wrong, summing up Monaco’s misery as the ball looped beyond Subasic on 77 minutes.
Germany international Draxler rounded out the demolition, firing home via a deflection as PSG clinched the title at home for the first since 1994 while shattering Monaco’s 17-match unbeaten run.
Earlier, Florian Thauvin struck a late winner as Marseille twice came from behind to beat struggling Troyes 3-2 and stay in the hunt for a Champions League place.
Marseille were reeling after Samuel Grandsir headed Troyes ahead with just 37 seconds gone at the Stade de l’Aube, but Clinton Njie’s scuffed effort soon pulled the visitors level.
The 41-year-old Benjamin Nivet fired Troyes back in front just after half-time as the veteran skipper followed up a rebound after Yohann Pele had saved from Grandsir.
But a clinical finish from Greece striker Kostas Mitroglou made it 2-2 with quarter of an hour to play, and Thauvin volleyed home his team-leading 17th league goal on 86 minutes to cap a dramatic victory.
Rudi Garcia’s Marseille remain level on points with third-placed Lyon, who occupy the final Champions League spot, while Monaco are four points ahead of the chasing duo.