McIlroy had birdies on each of his final five holes in Dubai, United Arab Emirates, Sunday in holding off Justin Rose. It was McIlroy's second European Tour title of the year along with the PGA Championship, which counts on the European Tour.
He pushed his 2012 winnings to a European Tour record $7.1 million.
Rose turned in a course-record 10-under 62 in Sunday's final round and finished second in Dubai. That allowed him to move up three places in the rankings to fourth. It was the only positive move in the rankings' Top 10.
McIlroy has a rankings points average of 13.608, more than four points ahead of No. 2-ranked Luke Donald (9.282). Donald finished 2011 ranked No. 1. Tiger Woods has an average of 8.885 for third in the rankings and Rose moves to 6.658, which is fourth.
The first event on the 2013 European Tour schedule is the Nelson Mandela Championship in South Africa Dec. 6-9. The PGA Tour 2013 season begins with the Hyundai Tournament of Champions Dec. 31-Jan. 7 in Hawaii.