The 34-year-old from Hertfordshire shot a three-under-par 67 in the final round to finish one stroke ahead of Malton's Simon Dyson and Italian teenager Matteo Manassero.
Despite enjoying one of his best seasons to date in which he won the WGC-Accenture Match Play Championship and played a pivotal role in Europe's Ryder Cup triumph at Celtic Manor last month, Poulter dropped down the rankings and by the time he arrived in Hong Kong he was 14th in the world.
However, he was in red-hot form throughout the tournament – with a fine 10-under 60 in the second round the highlight – and thoroughly deserved a victory that moves him back inside the world top 10.
Poulter is confident he can now climb even higher, but after causing a stir among his fellow pros two years ago by insisting he was the only serious challenger to then No 1 Tiger Woods when at his best, he was this time keeping his cards very close to his chest.
"I'll try and win next week first (at the Dubai World Championship)," he said.
"I'm not playing the game saying, 'I'm going to get to No 1'. I tried that once before and it didn't work.
"I think I'll just try winning next week and see how high I can go. Tiger has dropped a lot of points and (Lee) Westwood is world No 1but if I keep playing well, then who knows? I could get up there."
Victory never really looked in doubt for Poulter, who had been consistently impressive since firing his second-round 60, and expected challenges from the likes of Graeme McDowell and Rory McIlroy failed to materialise.
"To be honest, I felt comfortable all day," he added. "I felt very calm and very relaxed.
"The way I was hitting it, I was hitting it inside 12 feet pretty much nearly every hole out there. I knew if I kept doing that, I'd be very tough to beat."
Dyson had been Poulter's only real challenger after reeling off an eagle three on the par-five third before adding three birdies over his next four holes to put himself within touching distance.
But he failed to build on that as he bogeyed the eighth and added just one more birdie coming home to finish with a five-under 65.
"Fair play to (Poulter), he deserved it," said the 32-year-old Yorkshireman, who was chasing his fifth Tour win. "He played brilliantly the past two days.
"I could have taken him a bit close if my putter had been hot on the back nine, but it wasn't, so never mind."
Dyson's strong finish sets him up nicely for next week's season-finale.
US Open champion McDowell had started the day two strokes behind Poulter but his challenge for the title never really materialised as the Northern Irishman finished with a two-under 68 to take fifth place.
A victory for McDowell would have been the perfect tonic ahead of the Dubai World Championship next week – where he hopes to be crowned Europe's No 1 – but he is nevertheless happy with his current form.
"No disappointments in general this week," he said.
"I am very happy with my form and very happy with the energy levels going into Dubai next week."
McDowell will have to finish in the top three of the Dubai World Championship this week just to have a chance of denying Ryder Cup team-mate Martin Kaymer the European Tour No 1 spot.
There is a difference of almost 250,000 between the two major winners with one event to go.
Fourth place next Sunday is worth 233,000 and would not therefore be enough for McDowell even if Kaymer finishes last.
If the Ulsterman does come third Kaymer would have to be only 20th to stay top, but if he is second the German would need to be third – and if McDowell takes the 776,000 first prize the money list title will be his as well.
There is a massive bonus of 932,024 for finishing No 1, so the US Open and US PGA champions could earn more than 1.7m next weekend.
It is down to the two of them. Westwood, last year's winner of both the event and the "Race to Dubai", is over 787,000 adrift of Kaymer in third place.
"I'm within touching distance now," he said. "I've got to play well, simple as that.
"I can't control Martin's ball; I can only control mine. I'm going to go in there next week and try to play my own game.
"I have a few things to brush up on before Thursday, but all in all, I have been driving the ball great, which is key to next week and I'm feeling really good about my game.
"I'm playing well enough to win next week and that's all I can ask."
Poulter's victory was a deserved one, with the Englishman having only recorded his first bogeys of the tournament today whilst also carding the best round all week with a 10-under 60 on Friday.
"He's a great player and it is great to see him back in the winner's circle here in Europe," added McDowell.
Compatriot McIlroy had narrowly missed out on victory at the Hong Kong Golf Club in the last two years but was never really in the hunt as the final round progressed, finishing in sixth following a 67.
"I'll go to Dubai a little bit disappointed but I know my game is in good shape," said the 21-year-old. "There were some good highlights this week but not enough.
"If I can take the good things to Dubai I think I'll have a good week."