The former Italy international feels the Juventus coach is on the same level as the Portuguese trainer after leading the Bianconeri to the Scudetto in his first season in charge
The 42-year-old Conte led Juventus through an unbeaten league season to clinch the Scudetto at his first attempt after making a move from newly-promoted Siena last summer.
"Antonio has clear ideas. They are not very complicated but they are effective," Vialli told Tuttosport.
"I put him on the same level as Mourinho, Mancini and Klopp. The thing that struck me most was his ability to convey a sincere and genuine sense of belonging at the club.
"It's been so long since I saw a relationship so intense."
Vialli also took time to discuss Juve's summer recruitment strategy, saying he wanted to see Napoli forward Edinson Cavani don the Bianconeri colours next season.
"You have to figure out how much money is available. If the budget is not a problem, I'd like to see Cavani in the Juve shirt," he admitted.
"Of course with [Robin] Van Persie you cannot go wrong, but I have a feeling that he will not come to Italy."