Watford and West Ham were also rumoured to be interested in welcoming the player's services. Juventus had accepted the Hornets' € 13 million bid, but Pereyra was not too excited by a possible move to the Premier League.
Napoli offered € 12 million plus bonus and Pereyra, 25, has opted to move to the San Paolo where he will also play some Champions League football next season.
Juventus believe they can cash in up to € 15 million for the sale of the Argentinean midfielder who failed to live up to expectations in the 2015-16 campaign.
Napoli are also negotiating the transfer of Antonio Candreva and have alrady registered the signing of Lorenzo Tonelli from Empoli.