Holland, who used to live and train in Leeds, crucially finished ahead of title rival Katie Zaferes of the United States to take the overall World Triathlon Series title.
The Olympic bronze medallist, 32, overhauled Zaferes during the final three kilometres of the run before coming home two seconds behind Australia’s Ashleigh Gentle.
Gloucester’s Holland said: “I can’t actually believe it.
“I thought at one point of the run that it was done because there was quite a big gap there. I can’t believe I brought it back in. This season as a whole has been absolutely incredible with three wins, two seconds and now the world title.”
Holland, who had never won a world title, said she considered retirement after winning bronze at the 2016 Rio Olympics but found an “extra motivation” that has carried her to the world title.
“This season for me had always been about the Commonwealth Games. That was what I had planned for all winter, that was what I was training for,” she said.
“Since that point, things have just fallen into place and I’ve just really enjoyed my racing.”
Yorkshire’s Alistair Brownlee, meanwhile, was disqualified in the final race of the World Triathlon Series yesterday after failing to go around a buoy during the swimming on the Gold Coast.
The 30-year-old two-time Olympic champion was initially hit with a 15-second penalty, which was subsequently upgraded to a disqualification.
Brownlee – the double Olympic champion – was not in contention for the world title heading into the event. Spaniard Mario Mola secured the overall title after finishing second. Vincent Luis of France crossed the line first, with Jonny Brownlee finishing eighth and Leeds’ Tom Bishop 22nd.
Alistair Brownlee tweeted: “Really disappointed with today. I thought I had a decent race in me. First ever DQ in any sporting event.
“Was on the wrong side of the buoy and I’ve seen it on video. But was disorientated after being hit and held under the water in the roughest swim I’ve ever done.”