Wie's 11th-hour birdie helped her break free from a pack of four players that included a heartbroken Jenny Shin of South Korea, who had led coming into the last before bogeying.
Birdie on last hole gives Michelle Wie dramatic win in Singapore
American Michelle Wie delivered when it mattered most on Sunday, draining a 40-foot putt for a birdie on the last hole to claim a dramatic one-stroke victory at the HSBC Women's World Championship.
All day long it had seemed as though a moment of magic was needed to lift the trophy, with so many players within sight of the lead at the Sentosa Golf Club.
But Wie's 11th-hour birdie helped her break free from a pack of four players that included a heartbroken Jenny Shin of South Korea, who had led coming into the last before bogeying.
Shin, 25, had one shot to spare from Americans Wie, Nelly Korda and Danielle Kang until fluffing her lines.
She found the sand, and then a bogey five for a seven-under 65 that left the door open for Wie.
With the victory, Wie claimed her fifth career LPGA title with a final-round seven-under 65, for a closing score of 17-under par 271.
"That has to be the best putt of my career," said an elated Wie, whose last win was the US Open in 2014. "It's been a tough journey but I'm just really proud that I pulled myself out of it."
There had been chances on the last for both Nelly Korda, 19, and Danielle Kang, 25, to force a play-off with Wie.
Kang went wide to end the day with a two-under 70.
Korda's gettable knock took a bend to the right and into misery and a one-under 71 for the rising star, who had looked so unflappable all week long.
Canadian Brooke Henderson then birdied the last for a 67 and a share of second on 16 under 272 with the pair.
Korda was consoled by sister and fellow LPGA star Jessica as she left the course. "It definitely hurts, but that's golf," Korda said.
Wie had been pecking away at the two players who had led the event for most of the day, and neither Korda nor Kang was ever able to break free from each other or from the field.
The two Americans were then overtaken by the surging Shin, who claimed the lead outright with a birdie four on the 16th after never really attracting notice until the business end of the tournament.
The trophy looked to be her's for the taking until that final hole. "The nerves that I got on 18, I think any human being would experience it," she said.
Benign conditions, apart from the heat, had helped ensure a series of low scores. The tournament and course record was broken by South Korean Kim Sei Young, whose 10 under 62 topped the mark of 64 set by South Korean Park Inbee last year.
Former world No 1 Lydia Ko of New Zealand was another to charge up the leaderboard early, opening with four straight birdies. But she found she had left her run too late as her five-under 67 left her at 12-under and tied for 10th.