The French side have agreed to pay a massive £38million fee for the highly-rated 22-year-old midfielder.
Pastore has signed a five-year contract with the Ligue 1 giants.
The French side have previously signed the likes of Jeremy Menez, Momo Sissoko, Salvatore Sirigu, Kevin Gameiro, Loris Arnaud, Milan Bisevac, Nicolas Douchez, Blaise Matuidi and Granddi Ngoyi.
Palermo president Maurizio Zamparini had claimed the deal was done on Friday. He told Radio Radio: “We closed the deal last night (Friday) around midnight. Basically it’s the official transfer of Pastore to Paris St Germain based on a €43m.”