Dimitar Berbatov looked to have earned Claudio Ranieri's men all three points when he netted with just 13 minutes to go but there was to be a late sting in the tail
Claudio Ranieri's men knew that nothing less than victory would suffice if they were to keep their feint championships hopes alive - at least until PSG played Stade Rennais later in the evening - and they took the lead through Dimitar Berbatov with 13 minutes remaining.
However, Fatih Atik equalised with just five minutes left to play and even though the visitors then lost Moustapha Diallo to a straight red card moments later, Monaco were unable to force a winner, thus handing the title to PSG.
Monaco had begun the game eight points off top spot, meaning they needed to win and then hope that PSG suffered a shock defeat at home to Rennes.
The latter scenario always looked unlikely but Monaco would have expected to have to seen off Guingamp, who should have been suffering something of a Coupe de France hangover after lifting the trophy at the weekend thanks to a 2-0 win over Rennes.
However, the visitors provided admirably stubborn resistance and Monaco appeared to have run out of ideas until Nabil Dirar made a terrific break down the right flank before driving in towards the box and the lofting the ball into the six-yard area, where Berbatov was waiting to nod home.
It was the Bulgarian's sixth goal in 10 Ligue 1 appearances for Les Rouges et Blancs and looked all but certain to draw Monaco back to within five points of PSG.
However, the Bulgarian was removed from the action on 83 minutes and just over 60 seconds later, Guingamp equalised.
It was a wonderfully-worked goal. Defender Baissama Sankho bounded forward down the right-hand side before picking out Mustapha Yatabare in the area. The Mali forward had has back to goal but he brilliantly laid the ball off first time for the supporting Atik, who instantaneously smashed the ball low past Danijel Subasic in the Monaco goal.
The hosts were stunned, none more so than Jeremy Toulalan, who was flattened by Moustapha Dalla moments later, the Senegalese earning himself a red card for throwing his head recklessly into an aerial challenge with the Monaco midfielder.
However, despite the numerical advantage, Ranieri's troops were unable to fashion any openings in the dying minutes, thus allowing PSG to clinch their second successive Ligue 1 title without kicking a ball.