Roy, who previously had his number retired by the Colorado Avalanche, is the NHL's only three-time winner of the Conn Smythe Trophy, awarded to the MVP of the Stanley Cup playoffs.
"It's a great day, it's a great honor to have the chance to come back with the organization and the family of the Montreal Canadiens," Roy said Thursday. "I think when you talk about the Canadiens, you have to put the word 'family' in front of it."
A fiery competitor, Roy parted ways with the team on bad terms during the 1995-96 season, forcing a trade after he was left in goal by head coach and former teammate Mario Tremblay during a blowout loss to the Detroit Red Wings on Dec. 2.
During Wednesday's press conference at the Bell Centre, Roy welcomed the opportunity to turn the page on the events that brought about the trade and hopes the team's fans will do the same.
"It was more difficult than people might think to leave Montreal," Roy said. "Yes, I would have liked to leave on a different note but there is nothing you can do today, and the message that I want to send is it's time for me to move on and I hope it is the same for them."
A four-time Stanley Cup winner, Roy led the Canadiens to his first title as a 20-year-old rookie in 1986. He won his second Cup and second Conn Smythe Trophy in 1993 as Montreal won a record 10 straight overtime games in the playoffs.
"I always have been proud of my 10 years in Montreal," said Roy, who starred in goal for the Canadiens from 1985 to 1995. "I learned a lot. This is where I learnt to be a winner."
Dealt to Colorado four days after his famous meltdown, Roy went on to claim his third championship with the Avalanche that spring. He added his third playoff MVP award and fourth Cup in 2001.
Roy, the winningest goalie in league history, retired following the 2002-03 playoffs. He was inducted into the Hockey Hall of Fame in 2006.
Colorado Avalanche president Pierre Lacroix said Roy's honor was well-deserved.
"To have No. 33 hang from the rafters in Montreal, a place where the game's greatest goaltender began his career, is truly special," said Lacroix, a Montreal native. "For me, it's another reminder of the legacy that Patrick has left behind. I know fans in the Quebec province appreciate his contributions and many will remember how far he came from his early days wearing the Canadiens sweater. We were able to witness the creativity and style that he developed and realized that he was in a league of his own at an early age."