The Northern Irish rookie held off home favourites Maximilian Kieffer and Marcel Siem with a final round of 70 to finish nine under par, two shots clear as France's Julien Guerrier also shared second place at Green Eagle Golf Courses.
It was only McKibbin's 26th start on the DP World Tour after graduating from the 2022 European Challenge Tour and he joined Darren Clarke in 2001 as only the second Northern Irish winner of this event.
He said: “It probably won’t sink in until tomorrow but to have my dad here, to win in front of him is pretty amazing.
“It was a great day, nice to go out and put a really, really nice round together.
“(I’ve learned) that I’m good enough to win. I always thought I was but to prove it today was pretty special.”
After his wild front nine on Saturday, which featured three birdies and three bogeys, McKibbin found a more conventional path to a three-under-par outward half of 32 on Sunday to emerge from a six-way tie for the overnight lead.
He did not capitalise on a brilliant approach from a fairway bunker at the third but made tap-in birdies at the fourth, seventh and ninth – as did Kieffer to stay one shot behind.
McKibbin dropped a shot at the 11th, where Kieffer made birdie, but the German bogeyed the 13th and 14th to give McKibbin a two-stroke lead – which was halved when he also took five at the 13th.
Kieffer holed a well-judged birdie putt at the 16th to increase the pressure, but McKibbin impressively got up and down from sand at the 14th to stay level.
The leaders were immediately joined by Siem, who had dropped a shot at the first but recovered with back-to-back birdies at the ninth and tenth before a superb bunker shot at the 15th set up another.
He gave that shot straight back after finding water off the tee at the next though, while McKibbin birdied the 15th.
Kieffer could only par the last to set the clubhouse target at seven under, matched by Siem after a closing birdie.
That allowed McKibbin some breathing space and after safely finding the 17th green for a two-putt par, he hit a wonderful approach to the last to finish the job with a birdie.
Victory lifts the 20-year-old from 92nd place to 23rd on the Race to Dubai Rankings in Partnership with Rolex.
Guerrier recovered a bogey at the sixth with birdie at the eighth but could only make pars from there until the last, where a birdie took him alongside Siem and Kieffer in second.
Frenchman Frederic Lacroix finished five under with the remaining third-round leaders sharing sixth place on four under.
Jordan Smith mixed two birdies and two bogeys on the front nine but a double bogey at the 15th ended the 2017 champion’s challenge. David Law parred his first 12 holes before a lost ball at the 13th led to the first of two consecutive dropped shots as the pair both shot 75, as did Alexander Björk and John Axelsen.