The 27-year-old completed his £44.3m (€63m )move to the Ligue 1 champions yesterday, less than 12 months after joining United from Real Madrid for £59.7m (€85m).
Di Maria’s United career started well, but dipped incredibly quickly and he only started one of the final 10 games of last term.
The Argentina international was said to have been left unsettled following an attempted burglary at his Cheshire home in February.
But he is much happier with life having sealed his move to the French capital.
“Things did not turn out well for me at Manchester United for many reasons, but that is the past,” the midfielder said.
“I have been in Paris for two days and I am delighted because I know my wife and my daughter will be happy here.”
As recently as June, Di Maria claimed he wanted to stay at United, but, at his unveiling in Paris, he conceded he wanted out of the club.
The former Real Madrid player insisted he was not the only man driving the deal through, though.
Di Maria claims United were happy to get rid of him too.
“This is not only my decision,” the player said.
“They (United) also wanted to sell me. It is a shared decision between the three parties, if we include PSG.
“PSG have been following me for several years. I am very proud to now be able to play for this great club, alongside such great players.”
Di Maria is the latest in a long line of South American signings made by PSG since their takeover by a group of wealthy Qataris four years ago.
The five-time French champions have signed David Luiz, Lucas Moura, Javier Pastore, Edinson Cavani, Ezequiel Lavezzi and Thiago Silva as they look to make PSG genuine contenders for the Champions League.
PSG beat Chelsea to reach the quarter-finals last season, but Di Maria hopes his new team can go all the way this year.
“The club has a very important ambition: To win the Champions League and that’s also my ambition,” said Di Maria, who won the trophy with Real Madrid two seasons ago.
“I will try to bring that little bit extra to help the team past the quarter-finals of the Champions League. I am delighted to come here to this city, to France and represent such an important shirt.”
Di Maria will have to wait up to three weeks to make his debut for the club as he is still recovering from a hamstring injury he suffered during the Copa America.
The sale of Di Maria, meanwhile, means United’s famous number seven shirt becomes available for the new season.
Summer signing Memphis Depay is favourite to take the jersey given that he wore it during his time at PSV Eindhoven.
United manager Louis van Gaal will now look to bolster his squad by signing Barcelona forward Pedro.
The 28-year-old has enjoyed 11 successful years at Barca, but has become frustrated at a lack of playing time at the Nou Camp recently following the signing of Neymar and Luis Suarez, who have formed a deadly three-pronged attack alongside Lionel Messi.
If Barca president Josep Bartomeu gets his way, Pedro will not be leaving the club, however.
”There is nothing on Pedro. There isn’t any official offer (on the table),” Bartomeu said..
”He is a Barca player and we want him to continue at Barca. To win the six competitions (we are in), we need the best players and Pedro is one of them.”
Meanwhile, United will learn who they will take on in the Champions League play-off round today.
Van Gaal’s side will face one of Club Brugge, CSKA Moscow, Lazio, Monaco or Rapid Vienna.
Celtic also feature in today’s draw in Nyon. The Scottish side are in the champions’ section of the play-off draw as a seeded team, and could face Maccabi Tel-Aviv, Partizan Belgrade, Malmo, Astana or Skenderbeu.