The Socceroos are trying to win the title for a second time and were again solid rather than spectacular in getting the job done in a niggly last-16 encounter in Doha.
Two goals in the first half, a deflected own goal on 12 minutes and a diving header by Martin Boyle on the stroke of the break, put Graham Arnold's side on their way.
With Indonesia out of gas at the end, Craig Goodwin volleyed in a rebound on 89 minutes for 3-0 and defender Harry Souttar made it four in stoppage time.
The scoreline flattered Australia but it was their third clean sheet in four matches and they have conceded only once.
Roberto Mancini's Saudi Arabia face Jurgen Klinsmann's South Korea on Tuesday for the right to meet them.
Indonesia were making their first appearance in the knockout rounds of the competition and were ranked 121 places below a physically imposing Australia.
They produced the first chance on six minutes when Netherlands-born attacker Rafael Struick prodded the ball first time narrowly over the bar.
Indonesia were behind soon after, Jackson Irvine crossing hard and low from the right and the ball flicking off the boot of defender Elkan Baggott and wrong-footing goalkeeper Ernando Ari.
Jackson Irvine (number 22) and his teammates celebrate Australia's goal in their 4-0 victory over Indonesia in Asian Cup 2023 round of 16, Jan. 28, 2024. Photo by Reuters |
Arnold puffed out his cheeks in relief midway through the half when Indonesia's Justin Hubner, who plays for the under-21 team of Premier League Wolves, let fly from distance.
Hubner, another born in the Netherlands, did not really get hold of it and goalkeeper Maty Ryan saved easily.
There was not too much in it for a lot of the half, a physical game reduced to niggly fouls and Indonesia twice letting fly with ambitious attempts that flew over the target.
Indonesia's vocal fans dominated at the compact Jassim Bin Hamad Stadium but they were silenced for a second time on 45 minutes when Scotland-born Boyle connected on a delicious Gethin Jones cross to stoop in for 2-0.
Mitchell Duke should have made it 3-0 with 10 minutes left but he missed the target with only the goalkeeper to beat, before Goodwin made the game safe.
Souttar headed in at the death to embellish the scoreline.
Debutants Tajikistan meet the UAE later Sunday, also in the last 16.