The Swedish international scored a double on his PSG debut, with his second an 89th minute penalty, to secure a last ditch point in a breathless encounter
An own goal from Maxwell gave the visitors the lead on four minutes, before Jeremie Aliadiere doubled their lead with a sumptuous second.
Ibrahimovic reduced arrears, but despite a host of chances and some shocking finishing from a number of players, it took a late penalty from the Sweden striker to secure a point.
After a fairly cagey opening few minutes, Carlo Ancelotti's men threatened to break the deadlock. Jeremy Menez was fed into space, but his low shot was saved at the feet of Fabien Audard before being cleared away.
From that clearance, PSG were caught napping. The visitors raced towards the other end of the field, and the quicksilver Kevin Monnet-Paquet delivered a cross into the path of Maxwell to stumble the ball into the back of the net, to give Lorient a shock lead.
Les Parisiens were renowned last season for their ability to hit back almost immediately after a setback, and that trend very nearly reared its head again.
Ezequiel Lavezzi forced Audard into a decent save, with a long distance strike, though the unmarked Ibrahimovic was perhaps the better option.
The hosts were much the better side, but failed to create space and negotiate a way past a water-tight Lorient defence.
A brilliant ball from Marco Verratti to Maxwell was intercepted by Bruno Ecuele-Manga, before Ibrahimovic headed into the side-netting from the resulting corner.
Alex subsequently spurned PSG's best chance of the game despite a pin-point delivery from a corner. Whipped in from the right, the former Chelsea defender headed wide, when he ought to have done better.
It could have been 2-0 midway through the first period when Alain Traore tapped home from close range, after good work from Aliadiere, only for the linesman's flag to intervene.
Somewhat surprisingly, Lorient were dominating and should have taken advantage of some woeful Parisian defending. Aliadiere and Traore were both found themselves in good positions to deliver dangerous crosses, but failed to capitalise, much to the frustration of the Lorient bench.
The visitors were unrelenting and were denied by a super stop from Douchez. A free-kick from Traore looked to be creeping into the top corner, but the former Rennes goalkeeper produced wonders to keep out.
Whilst many other teams would have been content to sit on their lead, Lorient were hungry for more and were rewarded with a brilliantly taken second just before half-time. Aliadiere received the ball from Lucas Mareque on the wing, before skipping past four defenders and slotting the ball under Douchez to seal the perfect opening 45 minutes.
Christian Gourcuff's side suffered an injury blow when Ecuele-Manga was withdrawn at half-time and PSG stepped up the ante with a bright second-half response.
The nerves of the home support inside the Parc des Princes could be felt and with the tension growing on the pitch, Lorient's goal began to lead a charmed life, with Ibrahimovic slamming an effort against the post.
Nevertheless, the goal finally did came. Ibrahimovic latched onto a lofted ball, beating the challenge of Gregory Bourillon, before finishing with aplomb to reduce the deficit.
An end-to-end encounter continued when the former AC Milan man produced a moment of brilliance to tee up Menez, but the former Roma man skied his attempt and not for the first time in the match.
The hosts threw everything at the visitors late on, with a number of chances going begging. But with the clock ticking down, Bourillon lunged in on Blaise Matuidi and the referee had no hesitation in pointing to the spot and showing a red card to the offender.
That left Ibrahimovic to step up and fire home an equaliser to spare his and PSG's blushes, at the start of an exciting new chapter in the French capital.