McIlroy ignited his final day charge with an eagle at the fourth hole, and after reaching the turn in 34 he reeled off five birdies on the back nine "“ including successive gains from the 17th "“ to finish on 14 under par.
It brought to an end a tumultuous few days for McIlroy who earlier in the week had announced that he and fiancee Caroline Wozniacki had called off wedding plans.
"I guess when I got inside the ropes this week, it was a little bit of a release, said McIlroy. "I was on my own and doing what I do best, which is playing golf, and that sort of gave me four or five hours of serenity or sanctuary or whatever you want to call it; just focusing on the job at hand which was to play golf and get the ball in the hole in the lowest number of shots possible.
"Yeah, I can't explain it. It's obviously been a week of very mixed emotions, but I'm sitting here looking at this trophy going, how the hell"‘"‘ how did it happen this week (shrugs shoulders) but it did (laughter). A great way to end the week obviously."
Not a great performer at Wentworth previously McIlroy suggested the changed conditions helped. "The rain. With it being so soft, it played a lot differently. Played into my hands. Played longer. Balls were bouncing off fairways into rough. You weren't getting big bounces on greens. You didn't have to try to play from front edges.
"You could play really sort of aggressive target golf out there, which isn't usually the style of golf that you need around Wentworth. But with the rain this week, that's what it turned into."
For McIlroy it was his 6th European Tour victory but interestingly just his first on European soil his others coming in Dubai (Twice), Hong Kong and the USA (twice).
McIlroy's victory, which was the first by an Irishman in The European Tour's flagship event since Harry Bradshaw in 1958 and the very first by a Northern Irishman, earned the 25 year old Ã¢Â‚Â¬791,660 and moved him to second place in The Race to Dubai behind Thomas Bjorn who started the today's final round with a five shot lead.
Lowry pushed his fellow Irishman all the way, but in the end he had to settle for second place on 13 under par, one stroke clear of two-time BMW PGA Champion Luke Donald (70) and overnight leader Thomas BjÃƒÂ¶rn, who triple-bogeyed the sixth hole en route to signing off with a round of 75.
Lowry holed a sixty foot putt at the last to edge clear of a tie for the runner-up position.
McIlroy's victory, a continuation of some very solid form this season, will move him to 6th in the World Ranking.
"I played well all week. I thought my short game was really good today when it needed to be, and I converted my chances when I got them. It feels great to win on The European Tour again. It's been 18 months since my last win in Dubai 2012, so it's probably overdue.
"It's nice to win again, and it's obviously a great event to win obviously. It's The European Tour's flagship event here at Wentworth, so it doesn't get much better than that."
Richard Green had another good week when he finished in a share of 16th position to follow his 3rd place finish in Spain last week and was the only Australian to make the cut after Brett Rumford had struggled early in the week.
h3. Leading scores:
274 R McIlroy (Nir) 68 71 69 66,
275 S Lowry (Irl) 64 70 73 68,
276 T BjÃƒÂ¶rn (Den) 62 72 67 75, L Donald (Eng) 71 67 68 70,
279 S Gallacher (Sco) 70 75 68 66, S Dyson (Eng) 69 74 69 67,
280 M Siem (Ger) 69 71 72 68, T Aiken (RSA) 68 72 70 70, P LarrazÃƒÂ¡bal (Esp) 69 71 69 71, F Molinari (Ita) 71 74 65 70, H Stenson (Swe) 68 71 71 70,
281 J Luiten (Ned) 70 71 67 73, C Doak (Sco) 69 72 69 71, A Levy (Fra) 71 73 70 67, M Kaymer (Ger) 68 75 69 69,
282 M Warren (Sco) 73 69 71 69, F Zanotti (Par) 67 72 73 70, R Cabrera-Bello (Esp) 65 73 73 71, J Blixt (Swe) 68 71 72 71, R Green (Aus) 70 73 70 69,