Brown shot progressively lower scores day by day (71 70 69 68) for a 278 aggregate which gave him a five-shot win over fellow Yorkshire county player Joe Dean.
The Lindrick man had been tied for both the second and third round leads, but had to share second spot with Belgian Alan De Bondt after a closing 73.
Jonathan Thomson, also Lindrick, had been tied with Dean for the halfway lead but slipped to 20th with a closing 78.
Brown showed his intent with a birdie at the first and added two more, at holes seven and eight, before dropping a shot at the ninth.
Coming home he had birdies at 15 and 18 for mirror nines of 34 and a win which precedes a Walker Cup get-together at Royal Lytham next week.
Brown and Huddersfield’s English amateur champion Nick Marsh are both part of Great Britain & Ireland’s provisional squad for the clash with the United States, which will be staged at Lytham in September.
Dean (72 68 70 73) had birdies at two and seven, but they sandwiched bogeys at both four and six.
Further bogeys followed on the way in, at holes 12 and 16, negating with interest his birdie at the 14th.
Thomson (71 69 76 78) dropped four shots in his first five holes and compounded the unfortunate start with a double bogey at the seventh.
He came home in level par with a mixture of both good, bad – and very good.
He had birdies at both 11 and 14, bogeys at 12, 13 and 16, and an eagle 3 at the 473-yard par-5 17th, which he played in four under for the tournament.