The resort - which also won the title in 2014 - beat Auckland, Bora Bora, the Gold Coast, Sydney, the Whitsunday Islands and the Yasawa Islands, Fiji, for the honour.
Destination Queenstown chief executive Graham Budd said the resort was now in the running for the title of world's leading destination, to be announced at the end of the year.
Of the most recent accolade, Mr Budd said it was ``wonderful''.
``A large part of the credit for this achievement should go to the tourism and hospitality operators that offer quality experiences for all travellers.
``Queenstown's stunning scenery, friendly and welcoming people, world-class activities, cosmopolitan food and wine offering and range of accommodation make Queenstown stand out as a must-visit destination for travellers from around the world.''
The World Travel Awards - now in their 23rd year - are voted for by travel and tourism professionals around the world.
Millbrook Resort, near Arrowtown, was for the third consecutive year named New Zealand's Leading Spa Resort.
Other nominees in that category were Kimi Ora Eco Resort (Kaiteriteri), Paihia Beach Resort & Spa Hotel, Pullman Auckland, The Langham Hotel Auckland and Wharekauhau Lodge (Wairarapa).
New Zealand was named Australasia's leading adventure tourism destination, ahead of Australia, Fiji, Papua New Guinea, Samoa and Tonga.
The grand final awards will be presented in the Maldives on December 2.
