Verratti, 24, has a contract with PSG until the summer of 2021, but speculation surrounding the Italian international continues to gather pace.
Barcelona and Real Madrid have both previously been linked with a move for the midfielder, but Di Campli has suggested that Italian champions Juve are strong players when it comes to the future of his client.
"I expect Juventus to do something special in the next transfer window," Di Campli told Tuttosport. "PSG want to keep Verratti at all costs.
"But it is clear that money is not enough. Appeal is also needed and in the last four years or so PSG have not done enough to improve in that regard. Juventus are a much more attractive option because big players want to be at winning teams."
Verratti moved to PSG from Pescara in 2012, and has won four Ligue 1 titles during his time in Paris.