The Barclays Premier League club have announced that Van Gaal, current coach of the Dutch national side, will take charge at Old Trafford after the World Cup with Ryan Giggs as his assistant.
Van Gaal, the 62-year-old former Ajax, Barcelona and Bayern Munich boss, has signed a three-year contract.
United executive vice-chairman Ed Woodward said: "In Louis van Gaal, we have secured the services of one of the outstanding managers in the game today.
"He has achieved many things in his career to date and Old Trafford provides him with a fitting stage on which to write new chapters in the Manchester United story."
The vastly experienced Van Gaal was quickly identified as the club's top target after David Moyes was sacked in April.
The appointment of Giggs, 40, ends speculation over the future of the club's most decorated player
Giggs had served as interim manager for the final four games of last season.
Source : PA
Source: PA