The talented Indian, who won the Yeangder Tournament Players Championship in Taipei last month, held off the combined challenges from American Jonathan Moore, who finished two shots back in second place after a 65, and Thai youngster Thitiphun Chuayprakong, who closed with a 70 to share third place with Bangladeshi Siddikur (66).
Bhullar, 24, was in control with an outward 31 to lead by three shots but bogeys on 10 and 13 opened the door for his rivals. A pumped-up Moore raced home with five closing birdies to apply the pressure but Bhullar responded like a true champion.
He drained a six-foot par putt on 17 to hold on to a slender one-shot lead into the last hole and then delivered a grandstand finish with a 12-foot birdie to become the first Indian winner of the Venetian Macau Open, which was being title sponsored for the first time by The Venetian Macau-Resort-Hotel.
"This is going to take a long time to sink in. I hit the ball so good. I was just in the perfect zone. More than that, it was self-belief. This is my first wire-to-wire Asian Tour title. I think it was more that I had to prove to myself that I'm a good front runner. I had to believe in myself. I did it and it was really special," said Bhullar, who earned US$118,875 for his fourth Asian Tour victory.
Bhullar, who had his country's leading amateur golfer Ashbeer Saini as his caddie, was flawless on the front nine with birdies on two, three, five and seven as he kept his foot on the pedal. The two dropped shots made his victory march a little more nerve-wracking especially when he faced a six-foot par putt on 17.
"I thought I was going to play relaxed in the last few holes. But Jonathan played really well. He holed a long putt on 17 "¦ I saw that. I had a good tee shot, missed on the left but the first putt, I hit it over the hole. Trust me, it wasn't an easy putt (coming back). I had to visualize the ball going into the hole a few times and that's what I did. I think the putt on 17 was the putt of the tournament. The whole week, I just struck the ball really well. Mentally, I was focused and I was in the zone. I knew I would win it easily," said Bhullar, who totaled 16-under-par 268 for the week.
The 20-year-old Thitiphun fought bravely on the front nine as he kept up with Bhullar with four birdies in his first six holes. But disaster struck on the eighth when he drove his ball out of bounds en route to a double bogey which took the wind out of his sail.
"I made some mistakes, especially on hole eight which cost me. I was under a bit of pressure and I wasn't sure of the wind direction. Then I chose my driver but I should have used a three wood which would have been better. That was my mistake," said Thitiphun.
"My feeling wasn't so good. My putting and driver, everything didn't feel too sure. However I am happy to finish tied third. I will try to become better from here. This week has been good experience. This will also help me earn my tour card."
Bangladeshi Siddikur finished strongly with four birdies in his last six holes for tied third as he snatched the last ticket to the WGC-HSBC Champions in China next month from the Order of Merit ahead of Scott Hend, who finished equal sixth.
"It was excellent putting and I hit the ball really well," said Siddikur, who needed only 22 putts in his final round. "I really wanted to get in to the HSBC. I was competing with Scott every day. It was really a good fight. My putting wasn't going in at the start of the round but I came back today. I just persisted."
Hend led the Australians in 6th position with Kieran Pratt and Wade Ormsby 14th.
Scores after round 4 of the Venetian Macau Open 2012 being played at the par 71, 6,
606 Yards Macau GCC course (a- denotes amateur):
268 - Gaganjeet BHULLAR (IND) 63-68-69-68.
270 - Jonathan MOORE (USA) 67-68-70-65.
272 - SIDDIKUR (BAN) 66-68-72-66, Thitiphun CHUAYPRAKONG (THA) 67-66-69-70.
274 - Shiv KAPUR (IND) 70-67-70-67.
275 - Angelo QUE (PHI) 68-66-70-71, Scott HEND (AUS) 65-70-69-71.
276 - Chinnarat PHADUNGSIL (THA) 71-72-67-66, Thongchai JAIDEE (THA) 66-68-73-69, Unho PARK (AUS) 69-68-70-69, Prom MEESAWAT (THA) 65-68-72-71, Adilson DA SILVA (BRA) 68-66-71-71, Berry HENSON (USA) 67-69-68-72.
277 - Wade ORMSBY (AUS) 73-66-71-67, Jason KNUTZON (USA) 67-68-73-69, Kieran PRATT (AUS) 66-68-71-72.