The Daily Mail reports that the new deal will see the 21-year-old striker earn £75,000-a-week at Old Trafford.
The youngster made 30 appearances and scored nine goals for United in the Premier League last season.
Welbeck also featured for England at Euro 2012 this summer.
What is your opinion? Feel free to discuss the article under. You have to comment by using your Facebook profile. Be fair and have respect for other people and opinions!
The reputation of the Premier League means it is the most popular and one of the most watched leagues in the world.
Five English clubs will compete in the last sixteen of the Champions League for the first time ever as Liverpool, Manchester United, Manchester City, Chelsea and Tottenham face some difficult away matches.