Italian Buffon, who joined PSG from Juventus in July last year, played 25 matches in all competitions and won a league title and French Super Cup in his season-long stay in Paris.
"Following joint discussions, PSG and Buffon have agreed to not renew the legendary goalkeeper's contract which expires on 30 June," PSG said in a statement on their website.
Media reports in England and France have linked Manchester United goalkeeper David de Gea with a move to PSG.
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Buffon, who was capped 176 times by Italy in a 20-year international career, said that the experience in Paris had helped him grow as a person.
"Thank you all for everything I have had the opportunity to experience in Paris. Thank you for the emotions that we have shared together," the 41-year-old World Cup winner said.
"Twelve months ago, I arrived at PSG filled with enthusiasm, welcomed by the incredible warmth of the fans... I leave happy to have enjoyed this experience which has undoubtedly helped me to grow. Today my adventure outside Italy comes to an end."
PSG did not reveal Buffon's next move but wished him success in his personal projects.
Buffon made his professional debut for Parma as a 17-year-old in 1995 before moving to Juve where he won nine Serie A and four Coppa Italia titles.
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