Kylian Mbappe scored a hat-trick as PSG celebrated winning the Championship with a 3-1 victory against Monaco at the Parc des Princes.
After failing to regain their crown in the past three matches, drawing one and losing two, PSG's sixth title in the last seven seasons and the eighth in the club's history was confirmed prior to Sunday night's game after Lille's goalless draw at Toulouse earlier in the day.
"I am delighted to see my team win the French Championship, one of the most prestigious in Europe," Tuchel told the club's official website.
"Celebrating this title in front of our home crowd makes it extra special, and it's a wonderful feeling to share with our supporters."
Mbappe punished his former club with three goals and the 20-year-old also saw a shot come back off a post, while Monaco saw several chances go to waste before Aleksandr Golovin finally found the back of the net for Monaco with 10 minutes remaining.
Only St Etienne (10) and Marseille (9) have won more Ligue 1 titles now than PSG, whose eighth championship puts them level with Nantes and Monaco.
"We're always so happy and proud to win a title as prestigious as the French Championship," Al-Khelaifi told the club's official website.
"Ligue 1 is the flagship competition here in France, a country at the very top of world football since last summer.
"That alone shows the huge importance we will always give to trophies won here in this great football nation. I congratulate my players, the coach, the staff and everyone at the club who work so hard behind the scenes.
"Furthermore I would like to especially thank the supporters for their loyalty and unrivalled dedication. Their passion for the club is extremely important for us."