The Spaniard believes his side have the right mentality to challenge champions Juventus this season but Rafa Benitez has warned they face a gruelling campaign in Serie A
The Partenopei have finished runners-up to Juventus in the previous two campaigns but have begun 2013-14 in fine style with a convincing 3-0 win over Bologna.
And Callejon, who moved to Stadio San Paolo along with Gonzalo Higuain and Raul Albiol from Real Madrid this summer, believes the squad are in the right frame of mind to challenge Antonio Conte's men this term.
"We can win the Scudetto," he told Corriere del Mezzogiorno. "It’s not going to be easy and it’s a long season but we have the right mentality to win."
Callejon went on to praise new boss Rafa Benitez, claiming that he - along with Chelsea's Jose Mourinho - is one of the finest tacticians in the game.
"Benitez is very different [to Mourinho] but as characters and with their working methods, they are the best in the world.
"They have the same ideas when it comes to keeping the group together."
Benitez himself echoed the 26-year-old's thoughts on the club's current mentality, though he warned that they face a gruelling season ahead.
“The Italian league is long, very long, and tomorrow's match [against Chievo] is already a difficult challenge," he told a press conference.
"What matters is having a winning mentality and to always play well. On the field is where we have to prove it."