Aiken held a three-shot lead going into the final day thanks to a third-round 62 and was never caught, even though playing partner Liang Wenchong carded a hole in one on the seventh.
India's Gaganjeet Bhullar also threatened to claim a popular home victory at the Jaypee Greens Golf Club he represents, twice getting within two shots of the lead as he recorded a superb closing 64.
But Aiken held his nerve and finished in style with a birdie on the last, carding a flawless 67 to finish 23 under par, three ahead of Bhullar with Liang (69) a further two shots back in third.
The 29-year-old from Johannesburg, whose previous win came in the 2011 Spanish Open, collected the first prize of £260,000 and is the sixth South African winner on tour this season.
"They just kept coming at me today [Sunday]," Aiken said. "I tried my best to get a little bit of a lead but couldn't get it going, everyone was holing everything; Liang on the front nine and Bhullar made some amazing birdies coming in.
"By no means was it a walk in the park. Finally I can have a bit of a breather."
A breather Aiken could certainly have done without came on the 18th tee, where he endured a 12-minute wait due to a prolonged ruling in the group ahead after Australian Scott Hend had driven into the water.
"It's not the easiest tee-shot in the world but I managed to hit a fairly decent one," Aiken added at the prize-giving ceremony. "I didn't really want to miss the fairway because I have been getting fliers out of the rough all week and I got another one, but it worked out well.
"I have been playing very nicely the last four months, making very few mistakes but not sinking enough putts. This week a few went in and I hit some better iron shots and I played phenomenal golf; two bogeys the whole week and overall I am very pleased with the way I played."
Aiken's only two bogeys came on the seventh and eighth holes of his second round, meaning he played the last 46 holes without dropping a shot and carded a total of 21 birdies and two eagles during the week.
Although Bhullar began the final round with three birdies and an eagle in the first five holes and Liang was also three under through five, Aiken crucially kept his nose in front with birdies at the second and fifth.
Liang then suffered a double bogey on the sixth before bouncing back in spectacular style by holing his tee-shot on the next with an eight iron, but Aiken remained unruffled and picked up three shots on the back nine to seal an impressive win.
"I played aggressively and I needed to make a good charge to have a chance. I made only one mistake on eighth, where I missed the fairways. But that happens," said Bhullar.
After missing out on his fifth Asian Tour title, the talented Indian hopes that it will not be long before he finds his way back into the winner's circle again.
"Basically no one remembers the second place guy after sometime. It is only the winner who stays in the history books. Being second or 40th does not matter. I wanted to try for a win and my caddie kept motivating me. For instance my friends, fans and some may remember I was second here, but Thomas Aiken's name will be there in the books," said Bhullar.
Meanwhile, Liang revealed he was pleased with his overall performance at the tournament.
"To card a double-bogey on the sixth and make a comeback with a hole-in-one on the next hole showed lots of character," said Liang
"I was two back at that point of time but unfortunately, I could not make as many putts as I would want to. But that's golf. You win some and you lose some. I tried my best and that's all I can ever ask for," added the Chinese.
Liang celebrated his last Asian Tour win in India in 2008 by winning the Indian Open where he also established a new low 18-hole score by carding a 12-under-par 60 in the opening round.
While he could savour the winning feeling again after faltering home with two bogeys against two birdies in his outward-nine, the Chinese believes his performance bodes well for his season ahead.
"I had a great week in India. Although I did not win, I learnt a lot about myself especially today. This is only my second event of the year and with such a great result, I'm sure it can only get better," said Liang.
Starting the day four shots back of Aiken, Kiradech stumbled with a bogey on his second hole but got straight back into the mix with four successive birdies starting from the fourth hole.
"I was only two behind after 10 but both Liang and Aiken were also at the top of their game. I tried to stay very close but it didn't really work out the way I wanted," said Kiradech.
Kiradech could not maintain his impressive run as he marked his card with another bogey and a birdie in his outward-nine and had to eventually settle for a 69.
"Aiken's a very good player. He hit a lot of solid shots and I'm honoured that I could play alongside him. But I'm really happy with the way I've played and I feel more comfortable. I believe I can finish the season in a high position," added Kiradech.
England's David Horsey shot a final round of 67 to finish in a tie for sixth with Hend (70) and Scotland's David Drysdale (71), while Spain's Alvaro Quiros (73) was joint 56th on his first start after a four-month injury lay-off following wrist surgery.