Thailand's Prayad blew a five-shot lead and the chance to win his second tournament at home this month as Hend carded a sparkling eight-under-par 64 for a total of 20-under-par 268 to win his third Asian Tour title by three strokes.
South Africa's Bryce Easton, playing his first Asian Tour event, also shot a 64 for a 17-under 271 to take second place while Prayad finished a shot further behind on third with a final-round two-over-par 74 at the Alpine Golf Resort-Chiangmai.
"To be honest, I didn't think I had a chance to win," the 40-year-old Hend said after picking up his winner's cheque of £88,790. "I played with Prayad the first two rounds and he was hitting the ball great and putting great.
"Obviously he played great yesterday again and I thought he would continue with the way he was playing. I was just looking for a solid top-five finish. Obviously it all fell together and I played quite well.
"Unfortunately for the other guys, they didn't quite keep the pace going which was good for me."
Thailand's Thongchai Jaidee, who needed a win to have a chance of qualifying for the Masters, finished tied 10th after a 72 while South Africa's Ernie Els finished tied 14th.
Having led the event after each of the first three rounds, Prayad's day went from bad to worse as he followed up a bogey on third with a double bogey on the seventh after driving into the water. Two further bogeys allowed Hend to take advantage.
"My irons were no good. The second shots were always reaching the fringe on almost every hole," the 47-year-old, who won the Thailand Open earlier this month, said.
"My feeling was okay when I started the final round. I'm not angry now although I had a chance to win."
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