Beckham, 37, revealed he will play without a salary at PSG, instead donating what he would have earned to a children's charity in Paris.
He has signed a five-month contract and confirmed the presence of Carlo Ancelotti and Leonardo, the head coach and sporting director, had persuaded him to join the wealthy French giants.
Beckham knows both men from time he spent on loan at AC Milan.
"I'm very lucky. I'm 37 years old and I got a lot of offers, more now than I've probably had in my career. I'm very honoured by that," Beckham said at a press conference.
"I chose Paris because I can see what the club are trying to do. I can see who the club are trying to bring in.
"It's an exciting city and now there's a club that's going to have a lot of success over the next 10, 20, 30 years.
"I'm very honoured I've been picked to be part of the future of PSG.
"Every club I've played for throughout the world I've been successful with.
"I was successful with Manchester United and always said I'd never want to play for another English club.
"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 honoured by the offers I had from other Premier League clubs but I didn't want to play there unless it was for Manchester United."