Substitute Paul Smyth scored a late winner to condemn Blackburn to a sixth home defeat of the season and earn QPR a 1-0 win.
Despite coming into the game on a run of four victories in five, Blackburn have struggled on their own turf, picking up just four points all season.
That frailty felt likely to appear the longer the game remained goalless and Smyth did the damage just six minutes into his introduction with a superbly directed header for his third of the campaign and he almost added another at the end with a sumptuous volley that rattled the woodwork.
But QPR held on for back-to-back wins to propel themselves within two points of the top six.
Blackburn should have been ahead at the break but Andri Gudjohnsen somehow hit the post from close range and they paid the heaviest of prices.
The hosts have been guilty of sluggish starts at home and they threatened similar here as QPR made the early running. A hopeful ball forward for the visitors found Ilias Chair who jinked onto his left foot before rifling a low shot that Aynsley Pears saved.
Little over one minute later, they were in again as Pears parried Rumarn Burrell's cross into the path of Karamoko Dembele whose effort was desperately blocked.
Their bright start was disrupted by a lengthy stoppage after an accidental collision between Steve Cook and his goalkeeper Ben Hamer who had to be replaced by Paul Nardi.
Despite QPR's superiority, Blackburn should have scored in the 41st minute when a slick move saw Ryoya Morishita cross to Gudjohnsen six yards out but with the goal gaping, he somehow struck the far post.
Rovers looked to gain more of a foothold after the restart but were indebted to Pears in the 55th minute when a routine long ball found Koki Saito bearing down on goal but his ferocious near-post drive was parried behind by the stopper.
It was Nardi's turn to shine moments later when Ryan Hedges crossed for Gudjohnsen who was coolness personified to create space in the box only for QPR's substitute goalkeeper to defy him with a wonderful close-range save to divert behind.
A series of corners caused panic in the QPR defence giving Hedges a sight of goal but he lashed into the side netting.
Those misses came back to haunt Blackburn as QPR hit the front with 12 minutes remaining when Chair's sumptuous cross picked out the unmarked Smyth at the back post to head across goal and into the left corner.
He almost added a spectacular second in the 88th minute when connecting with Sam Field's cross but his superbly timed volley cannoned off the post.
Blackburn's Valerien Ismael:
"Tonight is maybe the worst feeling I've had (here). We thought after the win at Preston that you can do the next step at home, you hope that you can get support, but it was completely the opposite.
"It was the typical 0-0 game. We've had the better chance until the 1-0, we should have scored in the first half and especially in the second half, the goalkeeper made a big save.
"Then we gave the goal away and that's the big frustration for me. The boys need to learn ok, not the game you can win but keep the point, 0-0, Championship, so many games, every point counts. You can build on some momentum.
"The goal was too cheap. We lost the ball in build-up without big pressure and that's the frustration for me.
"It's terrible. This one is painful because we didn't expect it. Big disappointment with the performance, how we gave the goal away."
QPR's Julien Stephan:
"(Smyth had a) strong impact, very strong impact. We expect from the substitutes the ability to change the game, be decisive and bring the French mindset in fact.
"It was completely the case. His behaviour, his mindset and how he is everyday in fact. It's an example for everybody, for all the young players.
"He didn't get on in the last two games but now he's made the difference and it's so important for us to have this kind of player, able to change a game, able to change a moment.
"So congratulations to Smythy, congratulations to all the players, credit to them for the victory."
