Ronaldo received the award from Pele and dedicated it to his family, but also paid tribute to the influence of United manager Sir Alex Ferguson.
He said: "It is an overwhelming moment, it is a dream come true and I would like to dedicate this to my family.
"I'm extremely happy, it's one of the most important moments in my life and I hope I can come back here again.
"After what I did in 2008, to receive this award is amazing and I feel very proud of this achievement.
"But it's also true that the manager always has an important role to play. It was a great season for me and for my club, and the coach was important for me because I learned a lot for him.
"His experience over so many years is of paramount importance - it's a privilege to have such a great club manager.
"This is the climax of a fantastic era for me. I'm happy and proud about what has been done by my team and what we have won.
"I am lucky to be part of the history of a club like Manchester United."