The Wallaroos threw their best shot at the Black Ferns before succumbing 37-12 in a loss compounded by an injury to captain Siokapesi Palu.
New Zealand winger Portia Woodman-Wickliffe scored three tries on her 34th birthday, her first after just 50 seconds in an ominous start on Saturday in Wellington.
But the visitors fired right back, Charlotte Caslick scoring with her first touch as the Wallaroos went blow-for-blow in the first 30 minutes.
Hard-running flanker Palu limped off after her foot was trapped under a pile of bodies holding up a Black Ferns try, while Caslick was also limping at fulltime after falling awkwardly in a tackle.
The Black Ferns led 10-7 at halftime, then hit top gear, former sevens star Jorja Miller's sensational solo effort a highlight as they improved their record against Australia to a remarkable 29-0 since their first meeting in 1994.
It was the Black Ferns' final game on home soil before August's World Cup, whereas the Wallaroos will play Wales in Brisbane and Sydney before departing.
"It's just building pressure and ... that self-belief is what we needed," said Palu, who was wearing a moon boot on her right foot post-game.
"Definitely a lot of positives in that first half to show that we can stay in it.
"It's just now trying to hold that out for 80 minutes."
Seventeen-year-old debutant Waiaria Ellis and fellow winger Desiree Miller were both enterprising, while No.10 Tia Hinds kicked well in tricky Wellington conditions.
Lydia Kavoa scored the Wallaroos' consolation try in the final moments, some rare joy after they had kept New Zealand's time in their attacking 22 metre zone to just five seconds in the first 30 minutes.
"We were not clinical enough (in the first half) ... credit to Australia they really tested us," New Zealand captain Alana Bremner said.
"I do (think we're ready for the World Cup). The internal competition is amazing, it grows and grows and we're pushing."
