The in-form Belgian, who has now scored seven goals in his last five top-flight outings, netted a brilliant free-kick seven minutes from time to complete his treble and deny Chris Ramsey's QPR a win that would have moved them above Villa into 17th place.
QPR's Matt Phillips scored the opener after just seven minutes at Villa Park, before Benteke's double put the hosts ahead at half-time.
Clint Hill equalised for Ramsey's men 10 minutes after the interval, and Charlie Austin put them in front in the 78th minute.
QPR were set to move out of the bottom three, but Benteke had the final say with a curling free-kick from 20 yards that left Rob Green with no chance and moved Villa above Hull City into 16th.
The visitors began the game quietly, but their first attack led to the opening goal.
Bobby Zamora worked space with his back to goal and went left before curling the ball over the defence for the unmarked Phillips to stoop and head home.
Villa were level almost immediately, though, as Benteke worked his own opening after cutting back from the left touchline and hit a shot that deflected off Steven Caulker's foot and over Green.
In a rare attack, QPR forced a corner that Villa twice failed to clear properly before the hosts broke to take the lead shortly after the half-hour mark.
Gabriel Agbonlahor flicked Carlos Sanchez's clearance on for Benteke, and the striker raced clear before calmly dispatching past Green from the edge of the area.
Jack Grealish, making his full Villa debut, tested Green early in the second half, before Hill glanced home Phillips' corner from the right.
Austin then shot straight at Brad Guzan as QPR sought to re-take the lead, and Benteke and Agbonlahor were not able to get on the end of Ron Vlaar's delivery.
QPR talisman Austin was not to be denied 12 minutes from time, however, as he smashed home Phillips' low delivery from close range.
But, fittingly, it was Benteke who stole the headlines from a pulsating clash with his fantastic set-piece with seven minutes to play.
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