The Young Socceroos came into the encounter on the back of a 6-0 drubbing of Philippines and took the lead just before half-time through Steve Kuzmanovski, who also scored a double in the group opener.
Only a minute after the interval Mario Shabow doubled the advantage and rounded out the 2-0 win for Paul Okon's side.
Australia is level on six points and goal difference at the top of the group with Japan - after identical victories against Laos and Philippines - with the Asian heavyweights meeting on Tuesday night.
The group winner automatically qualifies for next year's AFC U-19 Championship in Bahrain, while the five best runners-up also progress to join the host nation.
The Asian tournament also doubles as the 2017 FIFA U-20 World Cup qualifiers with the semi-finalists winning though to the Korea Repubic finals.
