Victory came in unsatisfying fashion, with rain intervening and Australia 19 ahead on Duckworth/Lewis, but they were worthy winners for the fifth time in a row in a triangular tournament which also included a well-beaten England - leaping from seventh to second in the world rankings.
When the sides met at the same venue six days ago Australia needed to make a world record chase on a day which saw 488 runs and 32 sixes; this time 121 for three from 14.4 overs was enough.
New Zealand had earlier posted a modest 150 for nine, confounding those who had written the ground off as a bowler's graveyard.
Ashton Agar did more that most to explode that notion, turning the game in his side's favour with three for 27, while D'Arcy Short proved batting had not become too treacherous with 50 from 30 deliveries to underpin the chase.
Colin Munro and Martin Guptill briefly threatened a repeat of last week's run-fest, helping themselves to a string of early boundaries to push the run-rate north of 10-an-over.
But once they fell in quick succession, Guptill toe-ending Billy Stanlake to mid-off and Munro attempting a second straight six off Kane Richardson.
Agar's return tightened the screw even further, Kane Williamson paying with his off stump for a hack across the line and Mark Chapman pinned lbw two balls later.
It fell to veteran Ross Taylor to keep the Black Caps in it and, while he held the fort for more than an hour an unbeaten 43 was not enough to make up for the regular clatter of wickets.
Agar bagged the last real danger man, Colin de Grandhomme for 10, with Andrew Tye and Marcus Stoinis also chipping in.
New Zealand hustled through four tidy overs at the start of the second innings but Short loosened the shackles in emphatic fashion at the end of the powerplay.
With 14 to his name from 15 deliveries, he went on to club his next six for 27 - including three on-side sixes.
A rain delay interrupted him in full flight and when play resumed, the Black Caps battled back.
With spinners Ish Sodhi and Mitchell Santner in tandem, backed by Munro's gentle seam, Australia went from 55 for nought at the end of the powerplay to 95 for three after 12 overs.
That still left them ahead of the D/L par and a pair of sixes - Glenn Maxwell off Sodhi and Aaron Finch against Santner - made it comfortable when the showers returned.
