The Socceroos are one of the worst movers following the release of the latest FIFA Rankings in light of the 2018 World Cup in Russia.
Australia have dropped seven spots down to 43rd in the rankings after claiming one point from three games at the World Cup.
The Socceroos had entered the tournament as the highest ranked in Asian Football Confederation (AFC) nation in 36th but have been surpassed by Iran (now 32nd).
Australia was leapfrogged by the Congo DR, Turkey, Bosnia & Herzegovina, Scotland, Montenegro and Greece.
Australia's 43rd place represents the side's worst ranking for 2018.
The side wasn't the only nation to suffer a major slide on the rankings, with 2014 world champions Germany falling 14 spots from first to 15th after their group stage exit in Russia.
France moves into first place after taking out the 2018 World Cup, while Belgium move above Brazil into second.
World Cup runners-up Croatia are the big movers, jumping 16 spots into fourth spot. Uruguay are also up nine spots into fifth, with England rising six spots into sixth.
The highest ranked AFC side is Iran (32nd) followed by Australia, with Japan (55th) and South Korea (57th) next best ahead of the 2019 Asian Cup.