Spurred on by a compelling run-a-ball 60 from Adam Gilchrist, the Australians chased down England's 242 for eight with 4.4 overs to spare and extended their winning run over the tourists following their 5-0 Ashes whitewash.
A bad night became even worse for England when it emerged batsman Kevin Pietersen, who top-scored with 82, had been ruled out of the remainder of the series after a delivery from Glenn McGrath broke his rib.
England, beaten 5-0 on home soil by Sri Lanka in their last one-day series, could not contain the Australian onslaught as Gilchrist and Matthew Hayden (28) pounded their attack.
Gilchrist hammered seven fours and a six but even when both openers departed in quick succession, skipper Ricky Ponting compiled a steady unbeaten 82 and Michael Clarke a measured 57 to steer them home with an unbeaten stand of 133.
After skipper Michael Vaughan won the toss and elected to bat, England slipped to 73-3 before a fourth-wicket stand of 95 between Pietersen and Paul Collingwood (43) lifted the tourists towards a reasonable total.
Pietersen, who looked a pale shadow of his confident self after the McGrath blow, holed out to long-on after an innings which included four fours and three sixes.
England lost momentum as Paul Nixon went for a duck and Jamie Dalrymple got a poor decision, adjudged caught behind for two when the ball came off his helmet, but Andrew Flintoff (47 not out) added useful runs at the end.
Nathan Bracken had made the early breakthroughs, dismissing openers Andrew Strauss (12) and Vaughan (26) both caught at first slip by Matthew Hayden.
Mitchell Johnson, playing his 11th one-dayer in the absence of an ill Brett Lee, had Ian Bell (15) caught at cover and took Nixon's scalp while Bracken removed Jon Lewis (9) in the run chase to finish with the pick of the figures, 3-46.
Australia play New Zealand in Hobart on Sunday in the second match of the series.
England 242 for 8 in 50 overs (Kevin Pietersen 82, Andrew Flintoff 47 n o, Collingwood 43; Bracken 3 for 46, M Jhonson 2 for 34, McGrath 2 for 40) lost to Australia 246 for 2 in 45.2 overs ( Ponting 82 n o, Gilchrist 60, Clarke 57 n o, Hayden 28; Dalrymple 1 for 38, Panesar 1 for 46)