PSG had to better Lille's result, but Lille won 2-1 at Angers and PSG won 2-0 at Brest in one of the most exciting French seasons for many years.
Lille have won the Ligue 1 title thanks to a 2-1 victory at Angers which ensured they were crowned French champions for the first time since 2011.
An early Jonathan David strike and Burak Yilmaz's penalty in first-half stoppage time ensured that Christophe Galtier's Lille finished one point ahead of second-placed Paris Saint-Germain, who won 2-0 at Brest.
Angelo Fulgini pulled one back in added time at the end of the match, but the hosts couldn't stop Lille becoming champions for the fourth time in their history.
"This is exceptional. It's been a long day and a lot of pressure.
To beat Paris Saint-Germain to the league title is something exceptional," Galtier said to Canal+.
"The players were amazing... the credit goes to the players, they are the heroes."
READ MORE: Yilmaz double against Lyon helps Lille regain top spot of France Ligue 1
Ten years later, we are back in dreamland: this is as real as it gets …— LOSC Lille EN (@LOSC_EN) May 23, 2021
Following our victory against @AngersSCO, we are @Ligue1UberEats 𝗖𝗛𝗔𝗠𝗣𝗜𝗢𝗡𝗦 𝗢𝗙 𝗙𝗥𝗔𝗡𝗖𝗘 ! ❤️ #Champions4You @NewBalanceFR @NBFootball pic.twitter.com/7uQH6ShZnA
The title triumph came after another away success for Lille, who finish the season unbeaten on the road since November, and ends a three-year league winning streak for PSG.
It was fitting that it was David and Yilmaz who scored the crucial goals at Angers, as both have been key to an improbable run to the title that has also held significant pressure from Monaco.
Canadian young gun David latched on to a superb Renato Sanches pass to coolly slot home his 13th of the league season with nine minutes on the clock, immediately calming any nerves after last week's disappointing draw with Saint-Etienne left them needing a win to make sure of the title.
David was the man who won the penalty that secured the points and the championship just before the break, Paul Bernardon bringing the 21-year-old down and allowing Yilmaz to score his 16th league goal of a remarkable season for the veteran Turkey striker.
READ MORE: Lille open six-point lead in Ligue 1 thanks to Turkish duo
Mauricio Pochettino's PSG will have to content themselves with the French Cup in a disappointing season for the Qatari-owned club.
Neymar had already missed a penalty when they took the lead at Brest thanks to a freak own goal from Romain Faivre, who somehow diverted Angel Di Maria's corner into his own goal from way out near his own touch line.
Kylian Mbappe made sure of the win in the 71st minute but by that time the destination of the title was already as good as certain.
"There are no worries. We lost the title and now we have to focus on the future," said Mbappe, who was crowned Ligue 1 top scorer for the third year in a row.
Monaco won the race for the final Champions League position despite only managing a goalless draw at Lens, as Lyon lost 3-2 at home to mid-table outfit Nice and allowed the Principality club to claim third spot.
Lyon will take part in the Europa League alongside fifth-placed Marseille, who lost 1-0 at Metz.