PSG fails to move level with Montpellier
PSG looked set to take full advantage of Montpellier's shock defeat earlier in the day when Nene put them ahead in the first half, but Auxerre hit back through Anthony Le Tallec with four minutes to go to salvage a point.
The draw does little to help Auxerre's bid to escape the drop as they are still five points adrift of safety, but for PSG it is another damaging blow to their title hopes.
Carlo Ancelotti's side beat Marseille last time out to end a three-match winless streak and the news that leaders Montpellier had lost 2-1 at mid-table Lorient in the afternoon would have been another welcome boost for the capital club.
And, knowing a victory over struggling Auxerre would see them join Montpellier on 66 points heading into the final six games of the season, PSG started well at the Stade Abbe Deschamps.
Hosts Auxerre had the first effort on goal in the seventh minute, PSG goalkeeper Salvatore Sirigu saving from Dennis Oliech, but the visitors came within inches of taking the lead four minutes later when Jeremy Menez smashed a shot against the post.
PSG did not have to wait much longer to go ahead, with Nene netting in the 23rd minute.
Kevin Gameiro threaded a ball through the middle for Nene, who controlled the pass before firing a powerful left-footed shot past Olivier Sorin.
That goal looked like being the match-winner as, despite creating a host of opportunities, Auxerre were still trailing heading into the last few minutes.
PSG custodian Sirigu was called on to keep out efforts from Alain Traore and Willy Boly just before the break and Kamel Chafni was unlucky in the 52nd minute to see his well-struck effort come back off the post.
Sirigu was back in the action in the 59th minute to push away a diving header from Oliech, and again 10 minutes from time to keep out a good long-range effort from Georges Mandjeck.
With time running out PSG looked like they might weather the storm, but Auxerre got the equaliser they deserved in the 86th minute when Le Tallec pounced following a goalmouth scramble after Sirigu had saved from Omar Kossoko.