Japan beat South Korea 3-0 in a penalty shootout after the two sides drew 2-2 in the first semi-final at the Al Gharafa Stadium.
"It is unreal, how can you expect to win like that?" Australia's beaming German coach Holger Osieck told reporters after his side crushed opponents who played the last 23 minutes with 10 men.
"We planned to win the game and get to the final but you can never predict a score like that.
"I'm very happy how our team has developed in the tournament and we are almost at the stage where we can compete and become champions."
Australia had been criticised for their failings in front of goal before the semi-final after scoring just one goal in each of their last three matches but they had little problem in finding the net against an Uzbek defence who played like strangers.
Australia took the lead after just five minutes at an half-empty Khalifa Stadium when Harry Kewell was afforded enough time to fire an angled left foot shot in to the opposite corner after a clever throughball from Matt McKay.
SENT OFF
Uzbekistan had produced some lovely pass-and-move football en route to their first appearance in the last four but were far from their best as David Carney went close to doubling the lead but his chipped-effort was blocked by Juraev.
The chances continued to come for Australia, at 26 the best FIFA ranked side in the tournament, and Sasa Ognenovski made it 2-0 in the 34th minute with a rifled finish from close-range after the ball fell kindly to him in a crowded penalty area.
Uzbekistan coach Vadim Abramov made two changes early in the second half bringing on Sanjar Tursunov and Marat Bikmaev but they were unable to stop the one-sided flow.
Overlapping fullback Carney was able to grab a third after he latched on to a throughball from McKay and slotted under Uzbek goalkeeper Temur Juraev in the 65th minute.
The Uzbeks started to lose their cool and Ulugbek Bakaev, whose two goals sealed a quarter-final victory over Jordan, was sent-off after he received a second yellow card for lunging on Luke Wilkshire two minutes after the goal.
The Uzbek defence continued to disintegrate and offer the Socceroos chances. Substitute Brett Emerton took full advantage after a long ball from the back found Robbie Kruse in space and he squared for the midfielder to easily finish in the 74th.
Midfielder Carl Valeri also converted from close range in the 82nd minute after another assist from McKay with Kruse completing the rout moments later after his tame side-footed effort from 25-metres out slipped embarrassingly under Juraev.
"I don't know exactly what happened. I am sorry for the Uzbek people," a despondent Abramov told reporters.
