The celebrations were particularly muted for an off-colour Edinson Cavani as the Uruguay international's wayward finishing, and Karl-Johan Johnsson's inspired goalkeeping, prolonged his wait to become PSG's all-time leading scorer.
Instead, it was an Adrien Rabiot header and a Lucas Deaux own goal in the space of four minutes that gave the hosts a two-goal lead midway through the opening period.
Marcus Thuram pulled one back from the spot late in the half and, after Javier Pastore restored the two-goal advantage after the break, Guingamp gained another glimmer of hope courtesy of Yeni N'Gbakoto's penalty.
That was to be the last of their joy, with Marquinhos heading in a late corner to confirm the holders' progression in spite of their star forward Cavani's worrying performance.
All eyes were on Cavani from the outset as he began his second attempt to break the record and his big moment appeared to have arrived in just the ninth minute, only for him to head wide from Yuri Berchiche's enticing cross.
Guingamp failed to punish that miss as, on the end of a counter-attack, Marcus Coco compounded a heavy touch by blasting his close-range finish over the bar.
Cavani's own loose control soon denied him another attempt on goal, but PSG did not have to wait long for their opener. Rabiot lost Jordan Ikoko at a 21st-minute corner and powerfully headed home Angel Di Maria's in-swinger.
And it was two in fewer than five minutes when the visitors were confounded once more by a Di Maria set-piece, midfielder Deaux this time diverting the low delivery into his own net.
Cavani's all-action first half continued with him inadvertently handling another good chance, before Guingamp goalkeeper Johnsson smartly tipped a dipping effort over the bar.
That save soon took on extra importance when a fast-arriving N'Gbakoto was adjudged to have been brought down in the area by Kevin Trapp, enabling Thuram to reduce the deficit from the spot.
Emery's side set about nixing any comeback after the restart, but Cavani's frustration only grew as Johnsson added to his highlight reel with a succession of stunning saves.
However, there was little the shot stopper could do to stop Pastore from nodding in Julian Draxler's cross to restore the two-goal margin in the 64th minute.
Cavani next scuppered a one-on-one by bizarrely looking to offload the chance, and that allowed Guingamp to again claw their way back into the contest with N'Gbakoto converting a spot-kick following Thomas Meunier's clumsy challenge on Coco.
But an engrossing match was finally put to bed late in normal time, Brazil defender Marquinhos heading in another Di Maria corner to put the seal on victory.