The 37-year-old, who enjoyed a 10-year spell at Old Trafford before moving to Real Madrid in 2003, signed a five-month deal with the Ligue 1 giants on Thursday.
The deadline-day move brought to an end two months of speculation regarding the midfielder's future, with West Ham, Tottenham and QPR all having previously been linked with the veteran.
"I was successful with Manchester United and always said I'd never want to play for another English club," Beckham told reporters at a press conference to announce his move to PSG.
"I had a lot of history with Manchester United. It's the team I support and the team I dreamt of playing for.
"I'm very honored by the offers I had from other Premier League clubs but I didn't want to play there unless it was for Manchester United."