Lille moved to 70 points but defending champions PSG can close the gap to just a point if they defeat Saint Etienne on Sunday.
Andy Delort headed Montpellier ahead in the 21st minute on Friday.
But Brazil’s Luis Araujo grabbed a deserved equaliser with five minutes left with a memorable half-volley.
Lille were unlucky not have taken the lead earlier in the game when a Benjamin Andre drive came back off the post in the 57th minute.
“We ended the match well with a grip on the game and putting a lot of pressure on them, but unfortunately we could only score one goal,” said Lille coach Christophe Galtier.
“We let some points slip away but we will take stock on Sunday at 10:55pm.”
Montpellier are a resolute side and have now gone 14 matches in all competitions without defeat.
They are eighth and still well-placed to claim a European place next season.
