Moussa Sissoko fired Newcastle to a sixth successive victory to extend QPR's dismal run on the road.
The Frenchman, captaining the side in the absence of the injured Fabricio Coloccini, won it 12 minutes from time with the only goal as the Magpies finally made the pressure tell and left the visitors still without a single Premier League point away from home.
Alan Pardew's men, who have not conceded a goal in 432 minutes of football, enjoyed the better of the game in front of a crowd of 51,915 but had been frustrated up until that point by poor finishing and the efforts of keeper Rob Green, who made a series of important saves.
However, there was heartache for Ryan Taylor, starting his first Premier League game in 993 days, when he limped off in tears after just 34 minutes.
Former team-mate Joey Barton was afforded a warm welcome on his return to St James' Park, where he spent four seasons before heading for the capital, as he led out the visitors wearing the captain's armband.
But there was an even more significant re-appearance for the home side with utility man Taylor starting his first Barclays Premier League game since a 1-1 derby draw with Sunderland on March 4, 2012 after two cruciate ligament injuries.
Sadly for the 30-year-old his afternoon was to last barely half an hour as he departed after going to ground in some discomfort with all the indications suggesting yet another knee problem.
But inside the 34 minutes for which he was on the pitch, it was he who had looked the most likely man to break the deadlock, prompting the home side forward and arriving late into the box to apply the finishing touch to a series of moves.
Unfortunately for him, he was unable to take either of the two gilt-edged opportunities which fell his way as Green tipped his curling 17th-minute shot over after Remy Cabella had picked him out on the edge of the box with an intelligent corner and then claimed his side-footed effort after Ayoze Perez and Cabella had set him up following full-back Yun Suk-young's misplaced pass.
Green had earlier enjoyed an escape when he blasted a clearance straight into Jack Colback and saw the ball ricochet just wide as he attempted to deal with Steven Caulker's underhit back-pass, but was more than equal to the task of collecting Cabella's tame 10th-minute shot after the Frenchman had linked well with Sissoko.
Both sides had penalty appeals rightly waved away by referee Chris Foy after Massadio Haidara went down under Sandro's challenge and Leroy Fer under Mike Williamson's.
However, Taylor's premature departure changed the game with the visitors sensing their chance and with Barton making an impact, they pressed the Magpies back.
Striker Charlie Austin, who had gone wide with a 13th-minute shot, failed to test keeper Tim Krul unduly three minutes before the break, although the Holland international had to be on his toes on the stroke of half-time to keep out defender Richard Dunne's looping header from a Barton corner.
Newcastle returned in determined mood with Sammy Ameobi and Cabella running at the QPR defence at every opportunity and meeting less than composed resistance, although Barton threw himself into the path of Ameobi's well-struck 48th-minute volley.
At the other end, Austin scuffed a left-footed effort on the full straight to Krul, but the traffic remained largely in the other direction, although with Green untested until he had to race from his line and block Perez's shot with his chest after Sissoko had played the youngster in with 57 minutes gone.
The keeper was fortunate to escape when he spilled Haidara's driven near-post cross three minutes later and was grateful to see Ameobi head wide as he arrived at pace to meet substitute Yoan Gouffran's 63rd-minute cross.
But the visitors were not content to defend and striker Bobby Zamora, who had earlier headed wide, had Krul back-pedalling anxiously with another effort from Karl Henry's 66th-minute cross.
Substitute Niko Kranjcar, who had replaced the injured Sandro on the hour, gave QPR fresh impetus but the home side still looked the more likely to score, with Perez testing Green once again with a first-time shot from Gouffran's 74th-minute cross.
But the stalemate was finally broken 12 minutes from time when Sissoko turned on Ameobi's pass to fire unerringly past Green and spark joyous celebrations on and off the pitch.