Pastore said it would be "sad" should Ancelotti decide to leave, but understands that managers and players coming and going is part and parcel of modern football.
"I would be sad if he leaves," Pastore told reporters. "I've had a very good relationship with him in the 18 months that we've worked together.
"However, those are the sorts of things that happen in football. You have to be ready for it.
"I would like him to stay as he's done great things for the club, but it's up to everyone to make their own decisions."
PSG can wrap up the Ligue 1 title by beating Valenciennes on Sunday.