Verratti has signed a three-year deal with the Qatar Stars League club, who have paid a reported €45 million ($48.31m) for the 30-year-old, according to the Italian media.
“I was very proud to wear the colours of Paris St Germain for more than a decade, to rub shoulders with so many great players, and to win 30 trophies,” Verratti told PSG’s website.
“Paris, the Club and its supporters will always have a very special place in my heart. I will be Parisian forever.”
Verratti, who has never played in Italy’s Serie A, joined PSG in 2012 from his hometown club Pescara. The Ligue 1 side paid €12m ($12.87m) for the then 19-year-old.
In 11 seasons at PSG, Verratti played in 416 matches, making him the club’s second highest appearance maker behind Jean-Marc Pilorget (435).
He helped PSG win nine league titles, a record in Ligue 1, and won both the Coupe de France and the Coupe de la Ligue six times.
“Marco will forever be linked to Paris Saint-Germain,” said Paris Saint-Germain President Nasser Al-Khelaifi.
“He has always been there for the Club, giving his whole heart on the pitch and achieving so many great things with us.”
Verratti has won 55 international caps, scoring three goals. He was in the Italy squad who won Euro 2020, starting the final in which they beat England in a penalty shootout.
Al Arabi finished runners up to Al Duhail in last season’s Qatar Stars League and have started this season with three draws. The Qatari transfer window remains open until Sept. 18.