The son of famed Olympic [ Images ] athlete Milkha "the flying Sikh" Singh, the 34-year-old shot a final round 70 to finish at 10 under par for the tournament as his main challengers fell by the wayside.
"I just can't explain this feeling, it's been a long seven years," said Singh, whose last victory came in Thailand in 1999.
"I've let so many tournaments go in the last few years and went in to today with reverse psychology, thinking that if I didn't win it didn't matter."
While the high winds that wreaked havoc on Saturday's third round at the Honghua Golf Club eased significantly for the final round, good scoring was still at a premium.
Spain's Gonzalo Fernandez-Castano dropped a shot at the 18th to fall to 70 for the day and finished second on nine under for the tournament.
"It was a shame about the drive on the 18th which cost a bogey because...I would have liked to have parred it to put pressure on Singh.
"But from all these things you learn and I think I am getting to be a better player because of it, step-by-step," added the 25-year-old.
Briton David Lynn, the leader after the second and third rounds, finished a shot further back after a disappointing 73 with four bogeys and three birdies.
"I feel I have let this one slip to be honest," he said. "I was trying to be patient but on the back nine, crunch time, I got a dose of the three putts at the wrong time."
Defending champion Paul Casey shot a 72 for a share of fourth place on seven under, along with fellow Briton Simon Wakefield and Australians Peter Fowler and Jarrod Lyle.
Singh was the first Indian to qualify for the European Tour in 1997 but, plagued by wrist injuries, he played without success until 2002 before returning to the Asian Tour.
He will take home a cheque for $300,000, dwarfing his earnings in the last three years.
The 34-year-old started the day in a tie for second but dropped a shot at the opening hole, before hitting back with birdies at the third, fifth and seventh.
At the 11th, his tee shot went into trees and a spectator picked up the ball and threw it away. The offender received a kick from another spectator but Singh maintained his concentration and found a shot that enabled him to save par.
From then on Singh was rock steady and, with Fernandez in the clubhouse two shots behind, he could afford three putts on the final green to claim victory.
"When I saw my competitor bogey the 18th, I decided to play it safe and not even go for the flag," Singh said.
Li Chao, the only one of 22 mainland Chinese in the draw to make the cut, shot a final round 78 to finish six-over for the tournament after carding par 72s for the first three rounds.