His official victory margin over Liberal opponent Nathalie Goguen was determined to be 77 votes.
Goguen had persuaded a judge to order a recount of the ballots in the riding of Saint-François, where the election-night count put Hébert ahead by 110 votes.
The Liberal hopeful said some ballots were improperly rejected while others that were counted shouldn't have been. She also said a count the morning after the Sept. 4 election showed Hébert was awarded 50 extra votes at one poll in particular.
The judicial recount concluded those 50 votes were in fact tallied in error and subtracted them from Hébert's total, but it wasn't enough.
The riding's chief returning officer, Marjorie Tyroler, said the mistake was "basically human error" and involved "absolutely no foul play."
Hébert is the former dean of medicine at the University of Sherbrooke and has been touted as a possible health minister in a PQ cabinet.
Had he lost in the recount, the PQ would have been reduced to 53 seats in Quebec's national assembly, while the opposition Liberals would have risen to 51.