The teams in black ensured a double in the marquee sevens event on Sunday as the New Zealand men also took the crown which had been won last year by Australia.
After a close showdown, Charlotte Caslick's Aussie women, who were the last team to beat the New Zealanders in the Dubai Sevens final in January but have like everyone else been unable to tame them since, ended up being ousted 26-17.
The Kiwis sealed their win with just 21 seconds left on the clock as Stacey Waaka sped in for her second try to make it an incredible 29 wins and four trophies in a row for the winners.
It was also their third world series final win in a row over the Aussies after victories in Cape Town and Vancouver.
Teen Bienne Terita had scored first for the Australians but she was later sin-binned after tackling Kelly Brazier off the ball and conceding a penalty try.
With an extra woman, Waaka scored for the New Zealanders but the inspirational Caslick went over to narrow the gap.
New Zealand's Michaela Blyde notched a converted try to make it 21-12 and Sariah Paki's unconverted reply proved too little too late.
"I love playing Australia, they make us a better team," New Zealand captain Sarah Hirini said.
The consolation for world sevens player of the year Caslick was a record-breaking weekend in which she'd become the first Australian past 150 tries in world series matches.
"It was another great final, just with the wrong outcome for us," said Australian coach Tim Walsh, whose team had earlier beaten Great Britain 21-5 in the semi-final.
"Hong Kong has been home to such an amazing tournament, showcasing what an incredible spectacle rugby sevens - especially women's rugby sevens - can be."
But Australia's men, the reigning Hong Kong champs, could only finish a hugely disappointing tied-11th as New Zealand went on to beat Fiji 24-17 in the final.
It was New Zealand's first Hong Kong title since 2014 and the team's 12th overall, second only to Fiji's leading mark of 19.
"We were all really disappointed with this weekend's performances," said Australian men's coach John Manenti.
"We let ourselves down with poor discipline throughout the tournament. The good news is we only have a week to wait to fix it in Singapore."
It was a landmark tournament for Nick Malouf, who played his 50th world series tournament on his return from injury.
