The 50-over skipper made an unbeaten 136 as South Africa got off to a winning start in the one-day international triangular series, which also involves hosts Zimbabwe.
After Aaron Finch's century had set up Australia's imposing total, De Villiers came together with Faf du Plessis with the score on 51-2 at the end of the ninth over, and the pair proceeded to add 206 for the third wicket, with Du Plessis reaching his maiden ODI hundred.
Although Du Plessis departed for 106, JP Duminy's 33 not out saw South Africa home with seven wickets and 20 balls remaining.
"I haven't scored a lot of runs of late, so to score a few here is pleasing," said De Villiers.
"Two guys stood out today, first of all Faf. I know he's had a rough start to his ODI career, but he is in magnificent form. The other guy is Imran Tahir [who took 2-45 from his 10 overs].
"I think there is enough experience to carry the young guys through and carry them forward. I think the hunger we showed [was there], especially in the last series against Sri Lanka, and I was very pleased to see that hunger again today."
Du Plessis, meanwhile, was thrilled to reach three figures for the first time in an ODI contest.
"I got my first Test hundred against Australia, and to get my one-day hundred as well... I'm very happy," he said.
"I'm happy I got the opportunity to bat at three, it's important for me to get those hundreds. It's unfortunate I couldn't get over the line."
Losing skipper George Bailey, currently standing in for the injured Michael Clarke, was gracious in defeat, and defended the decision to replace spinner Nathan Lyon with opening batsman Phil Hughes.
"We certainly had enough runs on the board, and created enough chances, but hats off to Faf and AB, two extraordinary innings," he said.
"One of the challenges for us is Maxi [Glenn Maxwell] is a good enough spinner to not be a part-timer, like JP Duminy is for South Africa, and Steve Smith is going to be a massive one-day bowler for us."