A late goal from ring-in defender Robert Cornthwaite - his first for his country at senior level - gave the Socceroos a deserved come-from-behind victory that looked unlikely in the first half that was dominated by the home team.
The Socceroos were disjointed at times as coach Holger Osieck took the chance blood some young talent ahead of next month's East Asian qualifiers.
Osieck's starting team featured veterans Lucas Neill, Mark Schwarzer, Archie Thompson and Carl Valeri - who won his 50th cap - but the German also handed starts to Nikita Rukavytsya, Tommy Oar, James Holland and Ryan McGowan.
Cornthwaite partnered Neill at the centre of defence while Michael Thwaite was a surprise selection at left back for his first appearance in five years. Matthew Spiranovic believed to unavailable due to an injury concern.
Korea also fielded a youthful line-up featuring only three players with 10 or more caps but was the first to settle and took the lead after 12 minutes when striker Lee Dong-guk was left unmarked in the middle of the penalty areas and he found the net with a well-struck volley.
The home team was playing the better football and a few minutes later midfielder Ha Dae-sung just missed the upright with a low shot.
The Socceroos were being overrun in midfield but striker Rukavytsya gave the team hope with a positive run and stinging shot that narrowly missed the target.
Two minutes from half-time the Socceroos drew level when midfielder Tommy Oar picked out Rukavytsya and the striker found the far corner of the net with a low left-foot shot - to open his national team account.
The Australians played more cohesively in the second half with Osieck giving Aziz Behich, Tom Rogic and Eli Babalj their international debuts off the bench.
Valeri was forced off with an injury early in the second period with Behich introduced.
Exciting teenager Rogic followed, given his first cap when coming on for Archie Thompson in the 67th minute before Babalj and Leckie also joined in.
Captain Neill came agonisingly close to an elusive goal for his country when his header was tipped wide in the 73rd minute as Australia came home stronger and they secured a first win in Korea in 40 years when Cornthwaite popped up to score from a goalmouth scrap after Babalj's effort hit the post and ran across the goalline.
Osieck took plenty of positives from the performance, hailing a host of contributors who played key roles for the first time.
"I think it was good to win on the road but when you look at the team, I'm very surprised how well the boys did," Osieck said.
"And not only the ones who got their first cap today, even those who don't usually have much playing time.
"Everybody (did well) ... I'm very happy for those boys.
"I think we saw a lot of very positive elements that give us a lot of hope for the future."
While warning World Cup qualifiers were of "a different calibre" to the friendly, Osieck vowed to continue giving the young players a chance to develop in coming games.
"I think all in all I'm very pleased with what I saw tonight and we're going to build on it," Osieck said.
Cornthwaite, of Korean side Chunnam Dragons, admitted his head was spinning after netting the winner just two days after being called into camp.
"To come in and get on the scoresheet and get a win, I think was a great performance by all the boys," the defender said.
"It was a short preparation so I think the lads did a fantastic job tonight."