The 24-year-old arrived from Benfica at the start of the season for £62m and has played a key role in Pep Guardiola’s side taking back the Premier League crown from Liverpool.
Dias has featured 48 times across all competitions for Manchester City, who have also won the Carabao Cup and will contest the final of the UEFA Champions League against Chelsea in Portugal next week.
The Portuguese international is the first defender to win the award since Liverpool’s Steve Nicol 32 years ago.
Reflecting on his award, Dias said: "It's a huge privilege, I'm very, very happy. I could not have done it without the success of the team, without everyone in the team deserving this award. Only by that, as a defender, am I able to be here to receive this prize.
"Essentially, when I came I wanted to meet everyone as fast as possible, understand how the team plays. I knew the manager and the players, I knew a bit about the philosophy of the club because I am fan of football and I know City from the last few years.
"I had an idea of what I was coming to and I wanted to integrate myself as fast as possible."
"It means something because normally the ones who finish off the plays get the spotlight, but me receiving this award is a major example of our team," he explained.
"We work and build our game, it reflects the togetherness we have on the pitch. The spirit that runs through this team with these players, how we play like a family."