Paris Saint-Germain must close part of their stadium at the next Champions League game they host, as punishment for fans lighting flares and fireworks during their 2-1 loss to Real Madrid earlier this month.
UEFA says its disciplinary panel has ordered the north end of the Parc des Princes to be closed.
PSG have already qualified for next season’s Champions League and their next home game in the competition is likely to be in September in the group stage.
The Ligue 1 leaders must also pay a €43,000 fine.
PSG remain under a separate UEFA investigation for possible violations of financial fair play rules, with a decision in that case expected before June.