The match was decided in the first half itself as PSG hammered four goals in 14 minutes with Lo Celso scoring his two goals along with a goal each from Edinson Cavani and Angel Di Maria.
Rony Lopes pulled a goal back for Monaco but Di Maria struck his second goal of the match before Radamel Falcao scored an own goal and Julian Draxler added one more to PSG’s tally to complete a comprehensive win.
“It was important to win the title at home,” PSG coach Emery said. “We were able to show the difference between us and Monaco.”
With a fifth successive League Cup already won, PSG completed the second leg of a domestic treble – they are also through to the French Cup semi-finals.
PSG also became the first team in Europe’s top leagues this season to reach 100 goals.
Marseille come from behind aginst Troyes
In other Ligue 1 matches, Florian Thauvin struck a late winner as Marseille twice came from behind to beat Troyes 3-2.
Troyes opened the scoring after just 37 seconds thanks to a header by Samuel Grandsir. However, Clinton Njie soon scored an equaliser for Marseille.
Benjamin Nivet again put Troyes back in front just after half-time before Kostas Mitroglou made it 2-2 with 15 minutes left.
Thauvin scored the winner on the 86th minute to complete a dramatic turnaround.