City cruised to victory thanks to goals from Samir Nasri and Vincent Kompany to end the season two points clear of nearest challengers Liverpool.
It meant Pellegrini could celebrate a league and Capital One Cup double in his first season in charge with Hart, who was dropped and replaced by Costel Pantilimon for a spell after some below-par displays, praising the man at the helm.
"He's a winner, he wants us to win," Hart told Sky Sports. "He is a measured man and he believes in what he does.
"He is prepared to do what he needs to do to win the league and that showed.
"It's been a great year for me, a really exciting year. It emphasised what a squad you need to win the Premier League.
"I was having a tough time, Costel came in and did fantastic, and then proceeded to back me up. It's a big reason why we've won the league."
City timed their run to perfection, winning their last five games as Liverpool stumbled with the finishing line in sight.
"We came strong at the end, we won the games we needed to," Hart added.
"We are all winners, we have got strong personalities, we find a way for it to work."
Goalscorer Nasri added to the tributes to Pellegrini, saying: "I'm so happy for the manager because it's his first title in Europe.
"He remained calm the whole season. It was a pleasure to work for him.
"It's an amazing feeling. It's my second league in three years. It was an amazing league all year."