A sublime opener finished by Antonio Valencia and a ridiculous debut goal from substitute Javier Hernandez put United 2-0 up.
Salomon Kalou pulled a goal back late on and double-winning Chelsea threatened to level before Dimitar Berbatov sealed their fate in stoppage time.
Manchester United captain Nemanja Vidic is confident the Community Shield trophy is not the only silverware the club will be laying hands on.
He said after the game: "I believe there will be more (trophies) - this is just the beginning.
"I think we have a good squad and showed today we have energy and showed some hunger."
This summer Man Utd have had a tough schedule home and abroad, but they seem to be hitting their peak at the right time.
Newcastle, on the other hand, seem to be trying different ideas without much of it coming off. And this must be the quietest pre-season fixture list for Newcastle in many years.