The German sank a 2-foot putt for his sixth birdie in a 6-under 66 to finish at 21-under 267 at Abu Dhabi Golf Club and earn his fifth European Tour title. Poulter of England finished with a 66 after missing a 15-foot birdie putt to force a playoff.
Rory McIlroy of Northern Ireland was third at 269 after a 67.
“That was the nicest round of golf I have ever played on the European Tour,” said Kaymer, who has a metal plate in his right foot after breaking three bones in a go-kart crash last summer.
“All three of us played such good golf, we were going for the flags and going for everything. And to have come through that should be a real help if I make my Ryder Cup debut later this year.”
Kaymer won the Abu Dhabi title in 2008 and finished runner-up last year. Over his past 12 rounds in Abu Dhabi, he is 56 under.
Kaymer led by a shot overnight and opened the final round with two birdies to keep pace with Poulter, who picked up three shots in his first three holes.
After Poulter laid up with his second shot at the par-5 18th, Kaymer smashed a 3-wood from 277 yards on to the green. The German two-putted to take the $391,000 winner’s check.
Shane Lowry shot a 67 to be four shots back in fourth spot. It was the Irishman’s first top-five finish on the European Tour since turning professional after winning last year’s Irish Open as an amateur.