The World Number One arrived at Jumeirah Golf Estates for the season-ending event in Dubai holding a slender advantage over Ryan Fox in the DP World Tour Rankings in Partnership with Rolex.
But going into Sunday’s final round, McIlroy’s nearest rankings rival was U.S. Open Champion Matt Fitzpatrick – a fellow two-time winner at the Earth Course.
A closing four-under-par 68, coupled with a tie for fifth for Fitzpatrick at the final Rolex Series event of the year, ensured the four-time Major Champion topped the season-long standings again.
McIlroy’s Ryder Cup team-mate Jon Rahm became the first player to win the DP World Tour Championship for a third time as he finished two shots clear of runners-up Tyrrell Hatton and Alex Noren.
"It means a lot," he said. "It's been seven years I last did it. This is my fourth one but it's been a while, I've won three FedEx Cups since the last time I won this and it means a lot.
"I was a model of consistency the whole way through the year... just a really consistent season, I kept putting in good performances. It would have been nice to get a win in here at the end of the year but Jon put in an incredible tournament and fully deserved it.
"I'm really proud of my year and excited for 2023."
McIlroy first finished top of the season-long standings in 2012 and then won back-to-back Harry Vardon trophies in 2014 and 2015.
The 33-year-old, who had led the Rankings race since his runner-up finish at The 150th Open at St Andrews in July, also completes a rare double having won the PGA TOUR's FedEx Cup for a record third time in August.
Only eight-time winner Colin Montgomerie and six-time winner Seve Ballesteros now stand above McIlroy for Harry Vardon trophies.
"It seems like it's a long time since the Texas Open the week before Augusta when I was struggling a little bit and I made a couple of tweaks with my game and with my equipment," he added.
"I went to a different golf ball and it seemed like just after that my whole year turned around. I got a ton of momentum at the Masters and just went from there.
"One of the things that I'm really proud of the last few years is that I don't feel like I have to rely on one aspect of my game. If my driving isn't there my putter bails me out, if my putter isn't there then my iron play bails me out.
"When you get to this level you think, 'how can you make those incremental improvements to get better?'. And I think my goal has been to become a more complete golfer and I'm on the journey to doing that. I'm as complete a golfer as I've ever been and hopefully I can continue on that path."
Across the 2022 DP World Tour campaign, McIlroy’s worst finish in 10 events was a tie for 12th in the season opener at the Abu Dhabi HSBC Championship in January.
His fourth-place finish in Dubai this week was a remarkable eighth top five of the season and sixth in as many events.