The battle of last season's top two in the Championship ebbed and flowed throughout the pair's first top-flight meeting since 1995.
Norwich dominated the early proceedings at Carrow Road on Saturday and deservedly took the lead when skipper Russell Martin reacted quickest during a melee in the six-yard box.
Shaun Wright-Phillips saw a strong call for a penalty turned down seconds later as the west Londoners searched for an equaliser, which eventually came in the 59th minute when Luke Young struck his second goal in as many games.
The leveller came on the back of QPR boss Neil Warnock's wily introduction of Jay Bothroyd, but Norwich manager Paul Lambert played his own trump cards to secure the three points.
Having seen an attempt cleared off the line moments before, Holt was set up by fellow substitute Wes Hoolahan to net the winning goal to the delight of the majority of the 26,781 crowd.
The match started at a quick pace, with both sides eking out half-chances in the opening exchanges.
Third-choice QPR goalkeeper Radek Cerny - making his first appearance of the season due to injuries to Paddy Kenny and Brian Murphy - was called into action in the eighth minute when Simeon Jackson struck a well-hit shot from 20 yards.
The Canaries continued to press forward and in-form Steve Morison almost netted his fourth in as many games but, having wriggled past Anton Ferdinand, was thwarted by a low save by Cerny.
Fellow Wales international Andrew Crofts was the next to test the Hoops' backline, twice seeing shots deflect behind for corners.
The latter set-piece from Andrew Surman landed dangerously in the six-yard box and, after Ferdinand failed to clear, Martin reacted quickly to tuck home the opener.
The goal was just reward for the home side's dominance of the first 15 minutes, but they were fortunate not to give away a needless penalty almost immediately.
Wright-Phillips ghosted into the box and tumbled over the outstretched arms of John Ruddy, although referee Mark Clattenburg waved away the claims for a penalty.
The Rs were only impressing in fits and starts and the home side soon came close to doubling their advantage.
Morison, who was proving a handful for the QPR defence, found space on the edge of the box to unleash a curling effort that drifted just over the bar.
However, Norwich's attacks began to dry up as half-time approached and QPR began to enjoy more possession.
Shaun Derry almost connected with a whipped Wright-Phillips free-kick in the 45th minute, before the diminutive winger saw a shot saved by Ruddy and Jamie Mackie hit the rebound into the side-netting.
The second period started in much the same vein and Wright-Phillips almost netted four minutes in after a mix-up in the box between Ruddy and Leon Barnett.
The Rs, though, did not enjoy quite the same possession as they did at the end of the first half, leading Warnock to replace Clint Hill with Bothroyd in the 57th minute as they searched for a leveller.
The alteration paid dividends within two minutes as a speculative Mackie drive came back off the post into the path of Young, who slotted home from a tight angle.
The equaliser was no more than QPR deserved as they continued to look the stronger of the two sides.
As a result, Lambert brought on Hoolahan and Holt in attempt to change the path of the game and got the desired as in the 73rd minute.
After Holt saw a header blocked on the line by Young, the striker was not denied moments later found as he directed home Hoolahan's cross.
Norwich pressed for a third after regaining the lead but looked susceptible on the break, with Young almost capitalising as his cross clipped the bar.
QPR's push for another equaliser continued but resolute defending and wayward finishing allowed the Canaries to secure a victory that sees them leapfrog their opponents in the table.