France's Alexandre Kaleka, winner of the tournament last year, and Englishman Matthew Nixon were the closest challengers, finishing on 12 under.
Victory was Hoey's fifth European Tour title and represented a return to form after missing seven of his previous 10 cuts.
Hoey told europeantour.com: "I have absolutely loved the golf course this week.
"The putting was the key for me. I have been working hard on that a lot recently and the improvement is really showing because I making a lot of birdies.
"That is the main difference at this level. You have to be able to make a lot of putts because the standard is so high these days that it usually comes down to who makes the most putts.
"It's pretty amazing to think that I have won five European Tour titles.
"It is a great feeling to win and every time you do it you just want more and more. Hopefully I can get at least another one before the end of the season.
"It has given me a great boost. I am not the most consistent player in the world but when I get into these positions I usually do okay."
Hoey dropped just one shot throughout the day, at the 12th, and his lead was cut to two by Kaleka and Dane JB Hansen.
But his birdie at the 17th steadied nerves and Kaleka (bogey) and Hansen (double bogey) both dropped strokes at the last to card 68s.
Nixon came home in 33 and signed for a three-under-par 69, finishing tied second with Kaleka a shot ahead of Hansen.
Hoey said: "I did feel the pressure a bit today because I wasn't swinging it as freely as I had done yesterday but I got the job done in the end.
"Making my first birdie of the day on the seventh was a bit of a turning point because I had burned a few edges before that and you start to wonder if it is going to be your day."
China's Liang Wen-chong, Frenchman Gregory Havret and English pair James Morrison and Mark Foster finished in a tie for fifth on 10 under.
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