That means the former England captain, who signed a five-month deal with the Ligue 1 leaders, will likely be giving between £2million and £3million to a Paris children's charity.
Beckham, 37, said: "We decided on something quite unique. In this time I won't receive any salary. My salary will go to a local children's charity in Paris. That's one of the things we are very excited about and proud to do and something I'm not sure has been done before."
Beckham said he had not yet identified a suitable charity, and could not announce how much they would receive, except to say it would be a "huge sum".
"It's something the guys will decide, but it's a very good figure," Beckham said. "That's one thing we're very excited about. To be able to give a huge sum to a children's charity in Paris, it's very special."
The veteran midfielder, who recently moved to London from Los Angeles with his family, thinks the switch to the Parisian side could become a more long-term project.
He said: "I don't see that it's a short-term project. It might be a short-term project for me playing but there's a lot happening in this club with these owners. Whatever club I've gone to and whatever team Ive played for, I've worked hard. I don't expect to come into this team and play every game - I need to work hard.
"I don't automatically expect a place in the starting XI. I might have only signed a contract until the end of the season but I consider myself to be part of helping this club to grow, help the French league to grow and become one of the biggest powerhouses in football."
The former Manchester United, AC Milan and Real Madrid midfielder also explained how PSG boss Carlo Ancelotti and sporting director Leandro 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.