French internationals Ousmane Dembele, Randal Kolo Muani, and Layvin Kurzawa and Moroccan Achraf Hakimi were filmed singing an insulting song towards Marseille fans after a 4-0 victory at the Parc des Princes on September 24th.
"We let ourselves get carried away by the euphoria and we sincerely regret the words we should not have said and would like to apologise," the four said in identical posts on social media.
"We are well aware of the impact of our actions and our words on the public, notably the youngest who dream watching a football match," they continued, adding "in the future, we will do everything to further respect our duty to set an example".
Homophobic chants were also sung during this match by Parisian supporters for several minutes.
The club and its four players will appear before the French football league's disciplinary committee next Thursday, the day after PSG's Champions League trip to Newcastle.
The post from Dembele below can be translated on Twitter.