The goalkeeper says discussions are "going well" and admits he is unsure whether the club will look to sign a third player following the arrivals of David Luiz and Serge Aurier
The 27-year-old, who signed from Palermo in 2011, has less than 12 months remaining on his current deal at Parc des Princes.
While the Italy international says he is more concerned with the start of the new season - with PSG beginning their title defence against Reims on Friday - he has stressed his future will be settled soon.
"My renewal? It's being discussed, everything is going well and I don't think there will be a problem. But at the moment, it's the last of my concerns," he told L'Equipe.
PSG confirmed they had pulled out of the race to sign Angel Di Maria from Real Madrid on Thursday as they deemed the player to be "too expensive" given the constraints of Financial Fair Play.
While Sirigu admitted the Parisians could still delve into the transfer market before the window shuts, he underlined his belief that the two new arrivals so far this summer - David Luiz and Serge Aurier - would strengthen an already imposing squad.
"Last year, we already had a strong team, and two players have arrived. I don't know if there will be a third," he added.
"Aurier and David Luiz are great players who will certainly help us."