The Englishman, who was nine shots off the lead in the opening round, finished at 5-under 279 to beat Christian Nilsson of Sweden by one stroke.
Its unbelievable really, the 713th-ranked Dixon said. Its everyones dream to win a European Tour event. Its my first win, so its massive, an awesome feeling. I cant really get my head round it. Its going to take a while to sink in.
The 31-year-old Dixon had the best performance of the day with a bogey-free round, sinking consecutive birdies from the 7th hole to the 10th before taking the lead for good with a birdie on the 14th.
I took a bit of a gamble on the 14th, hitting a driver off the tee, then a 3-wood into the green, Dixon said. But they were two great shots, so it paid off handsomely.
Nilsson finished with a 71 after three bogeys over the last nine holes.
I thought level par would be enough today, but it wasnt, he said. David played really well, and 66 is a great score, so well done to him.
Steven OHara of Scotland was tied for second until he bogeyed the 17th to finish third, two strokes off the pace.
Seve Benson of England had a 67 to take fourth place, tied with countryman Richard Bland (68) and Frenchman Francois Delamontagne (71), three shots behind Dixon.
Robert Coles of England shared the lead with Nilsson after he birdied the sixth, but slipped to seventh place with a 283 total after three bogeys on the back nine.