Mitchell Marsh smashed an unbeaten 77 as Australia hammered New Zealand by eight wickets to clinch their maiden Twenty20 World Cup title on Sunday with captain Aaron Finch describing the achievement as "huge".

Chasing 173 for victory, Australia depended on a 92-run second-wicket stand between David Warner, who made 53, and Marsh to achieve their target with seven balls to spare in Dubai.

Warner became Trent Boult's second wicket but Marsh kept up the charge to power Australia home to their long-awaited T20 crown and add to their five 50-over World Cup trophies.

Glenn Maxwell, who made 28, joined Marsh, who hit six fours and four sixes in his 50-ball knock, to put on 66 runs and hit the winning boundary.

"This is huge, to be the first Australian team to do it. I am so proud of how the guys went about the campaign," said Finch.

"[Bangladesh game turning point?] Certainly was, backs were against the wall. We had to fight and certainly did that, had some great team and individual performances," he added.

Australia skipper also highly praised the performance of David Warner, Adam Zampa, Matt Wade and Mitchell Marsh.

"Can't believe people wrote Warner off a couple of weeks ago, it was almost like poking the bear. Zampa was the player of the tournament for mine, controlled the game, got big wickets, super player. Mitch Marsh, what a way to start, put pressure on from the start. Matt Wade came in under an injury cloud and got the job done. He came in the semi-final alongside Marcus Stoinis and did the business," said Finch.

New Zealand skipper Kane Williamson hit a valiant 85 in New Zealand's 172-4 after being invited to bat first in a crucial toss won by Finch. Teams bowling first won 12 of 13 matches played at the Dubai International Stadium.

Australia, whose previous best was a runners-up finish in 2010, came into this edition's semi-final with one loss to England and beat Pakistan in the final-four clash with a chase of 177.

Australia fast bowler Josh Hazlewood returned figures of 3-16 and leg-spinner Adam Zampa had 1-26.