The 18 year old put pen to paper on a new four year extension to his current contract with the club after having a successful season with the Reds last term, helping them to another league title.
This time around however, the youngster has found first team appearances harder to come by, but the United boss Alex Ferguson knows that the player has a bright future at Old Trafford.
'We are delighted by the new four year deal,' said the United boss.
'Everyone at the club recognises the fantastic talent he has and we hope to see that develop in the next years, so he becomes a well rounded player.'
Macheda said: 'I am very happy to commit my future to Manchester United. I really enjoyed myself last season when I came on and I hope to get more chances like that and contribute to the team's success.'