Lionel Messi looked to have curled in a fine winner in the 68th minute, but Lens dampened the already muted title party at the Parc des Princes through Corentin Jean with two minutes left.
PSG have an unassailable 16-point lead over second-placed Marseille with four matches remaining.
"The atmosphere is a shame," captain Marquinhos told Canal+.
"Football is our passion, we started very young. We'll try to have as much fun as possible. It's a shame that won't be with the supporters but we have to deal with it."
Mauricio Pochettino's men reclaim the crown from Lille, who were shock champions last season.
It is the capital giants' eighth Ligue 1 triumph in the last 10 seasons, powered by the investment of their Qatari owners.