The centre-back has hailed the veteran midfielder's positive influence and feels Europa League glory would see Juve return to the European top
Antonio Conte's men can take another step towards a domestic and European double on Thursday when they face Benfica in the second leg of their Europa League semi-final.
With their third consecutive domestic all-but-confirmed, Bonucci hopes Pirlo's influence can help the Bianconeri turn around their 2-1 deficit from the first leg.
"Pirlo's a leader - a silent leader, but one who knows how to carry his team through difficult moments," Bonucci told Uefa's official website.
"He showed that in Florence in the round of 16, ensuring that we won the match and progressed. He then also scored an important goal which helped us get past Lyon in the quarter-finals.
"Outside of football, he's a great man and has been one of the world's best midfielders in the history of the game."
Juve have not won a European trophy since the Champions League in 1996 and Bonucci claims victory in the competition would ensure Juve were back among the great teams in Europe once again.
"Since our last European trophy in 1996, we haven't been this close to winning a final, so for us it would be a source of pride.
"It would return Juventus to being one of the best teams in Europe."