The former England captain, who joined PSG on a five-month deal last month, came off the bench in the 76th minute to become the 400th player to represent the club from the French capital.
PSG were 1-0 up at that stage and Beckham then played a part in the injury-time Zlatan Ibrahimovic goal which clinched the win.
"I'm very happy tonight, mainly because of the victory," said Beckham.
"We have played better but it was very important to win. Today was the perfect day, not only because I'm the 400th player in the history of the club, but also because I'm part of a very special team.
"The welcome from the supporters was unbelievable, and I want to say thank you to them.
"It was a great match, the biggest in France. To have the opportunity at my age to play in such a great championship and with a great team, I am very happy and very proud."
PSG boss Carlo Ancelotti said: "He came on because Marco Verratti was tired and we needed fresh players on the pitch.
"He showed quality with his passes, his experience. He showed good qualities, even if it was difficult to judge in only 20 minutes."
Asked if Beckham could start against Marseille at the Parc des Princes on Wednesday in the in the Coupe de France, Ancelotti said: "Perhaps. Verratti is suspended, so maybe he will play."