The Frenchman, 28, has penned a three-and-a-half-year deal with the Ligue 1 champions.
It is understood that PSG have paid the Magpies around £20m for Cabaye.
"The club wanted to keep him but the lure of Champions League football and the prospect of being involved in the sporting project at PSG was an opportunity that Yohan made very clear to us he wanted to take," read a statement on Newcastle's official website.
"Yohan leaves the club with our best wishes for his future at PSG and, hopefully, as part of the French national squad for this summer's World Cup."
Cabaye joined Newcastle from Lille in 2011.