Caldwell, 37, was three shots off the lead before the final round and he carded an impressive 64, with eight birdies and an eagle on the 14th, to finish at 17-under overall to beat Spaniard Adrian Otaegui, who finished one stroke behind.
England’s Alice Hewson finished third a further shot behind while compatriot James Morrison and Australian Scott Hend finished tied for fourth, two shots behind her.
“It’s been a dream of mine for an awful long time,” Caldwell said. “A lot of hard work goes into it. It hasn’t quite sunk in yet, but hopefully more to come.
“In 2009 I played my first year, lost my card, played mini tours and Challenge Tour over the years, worked as well in a local golf store. It’s been a long road but finally I’m here.
The event, hosted by Annika sorenstam and Henrik Stenson, had a field of 78 men and 78 women vying for the same trophy and playing on the same course.
(Reporting by Rohith Nair in Bengaluru; editing by Clare Fallon)