كتب : Amro Hassan
The 20-year-old, who can play as a winger or in the centre of the pitch or as a striker signed a four-year contract with the Premiership club for a reported sum of £3 million.
"Gabriel is a player we have tracked for a few years now," United manager Alex Ferguson told the club’s website.
"We are delighted to get him now as he is an exciting prospect. We like to get young players and develop them and we will see that in Gabriel over the next two years."
Obertan is Ferguson's third signing during the off-season, after the capture of Ecuadorian winger Antonio Valencia and Michael Owen.
Watch United's new signing