The much-anticipated final round shoot-out between the Briton and the Australian failed to materialise as Ogilvy surrendered his two-stroke overnight lead on the first hole and plunged to third after wilting with a bogey-strewn back nine.
"It was flawless, the whole day. I was very happy how I approached every shot, hit my targets," the flamboyant Poulter said with the tournament's crystal globe trophy perched next to him.
"I love being in contention, that's why I play this game of golf. If you're down the field there's no adrenalin, there's no excitement, there's no real interest.
"So that's why I practise hard to put myself in this position to enjoy the fact of being under pressure because you find out who you are."
Australia's Marcus Fraser finished second after a scintillating 64 but was long in the clubhouse leaving Ogilvy as the sole realistic hope of stemming Poulter's victory charge.
Poulter, a model of composure throughout the tournament despite battling food poisoning on Friday and tricky winds over the weekend, threw down the gauntlet on the very first hole.
Landing his tee-shot on the green of the driveable par-four, Poulter drilled a 15-foot putt for eagle to draw level with Ogilvy on 13-under.
"Crucial... it was a very timely tee-shot," said Poulter. "The wind being as strong as it was, 25 miles an hour, it was a difficult shot... He gave me an opportunity there to try and roll it in to be all tied with 17 to play."
The 35-year-old then piled on the pressure with birdies on the seventh and ninth holes to take a two-stroke lead leaving Ogilvy scrambling.
On Saturday the Australian had lit up Victoria Golf Club, where he had been a member since his junior days, with a course-record equalling 63, but the magic deserted him as his approaches left him long, speculative putts that refused to drop.
Ogilvy grafted a pair of clutch putts to stay in touch in the middle stretches, but the pressure told as he conceded bogeys at 13 and 15 to go four down.
The Australian holed a long birdie putt on the 16th to briefly raise a slender hope, but Poulter slammed the door shut with a long birdie putt of his own to make the result a formality and add the tournament's 'golden jacket' to his colourful wardrobe.
The slumping loss left Ogilvy crestfallen and capped a disappointing year marred by injury and a winless season on the US PGA Tour.
"It has been a frustrating year," a stony-faced Ogilvy said."This is kind of how the year has gone, days like today.
"What are you going to do? I couldn't really make a birdie all day."
Poulter's 269 total secured him his first tournament victory since beating Luke Donald in the World Match Play Championship final in Spain in May.
World number one Donald capped his last week of golf for the year with a scratchy one-over 72 to finish joint 12th with a total of 280, 11 behind Poulter.
"I struggled a little bit the whole week, especially finding my line and speed on the greens," said the 34-year-old, the first winner of both the US and European Tour money lists in the same year.
"A little bit disappointing to finish like that but I'll reflect on what's been an amazing year for me."
Final scores from the Australian Masters (Players Australian unless otherwise marked)
269 Ian Poulter (Britain) 65 68 69 67
272 Marcus Fraser 70 69 69 64
273 Geoff Ogilvy 71 66 63 73
277 Adam Crawford 74 68 69 66
277 Peter Senior 69 70 68 70
278 Brad Kennedy 71 69 69 69
278 Kieran Pratt 67 70 69 72
278 Ashley Hall 66 70 68 74
279 Kurt Barnes 70 71 70 68
279 Peter Lonard 67 70 69 73
279 Nathan Green 69 68 67 75