Over 2,500 people attended, including former United greats Sir Bobby Charlton, Peter Schmeichel, Ole Gunnar Solskjaer, Andy Cole, Denis Irwin, Ruud van Nistelrooy, Edwin van der Sar and Eric Cantona.
And Ferguson's wife, Lady Cathy, stood next to her husband as she unveiled the new statue on Friday.
"Normally people die before they have a statue. I'm outliving death," joked the United manager to the crowd.
"It is an incredible journey I've had at the club. I have managed so many great players and some of them are here today.
"They should actually build a statue for all of them. They have been fantastic players to have.
"I have been very privileged to deal with such great players from 1986 through to today. They have given us all enormous pleasure.
"We all have a part to play, the manager, all the coaches and the medical staff. They have also played their part.
"I am really proud today. It is a fantastic honour. I would like to thank the Manchester United directors, owners and all the people involved in this decision."
Sculptor Philip Jackson said: "I've tried to portray him as a man of great determination and as a thinking man, but also with humour which he has in abundance, so there's just a slight smile in the corner of his mouth.
"That's really what I wanted to portray."