Australia, who were drawn in Group A along side Cote d'Ivoire, Argentina and Serbia, have included striker Archie Thompson, midfielder David Carney and defender Jade North to fill the overage roles.
"It was a difficult job selecting the team," Arnold said. "I had a look not only at current form of the players but their form right through the qualification campaign."
"The three overage players will bring both attacking and strong defence to the team," Arnold said.
"Finally, it is up to the whole team to play to the maximum of their ability."
Australia, who finishing seventh in 2004 Athens Olympics, will begin their campaign against Serbia on August 7.
The squad: Mark Bridge striker (Sydney FC), Billy Celeski midfielder (Melbourne Victory), Adam Federici goalkeeper (Reading, England), Neil Kilkenny midfielder (Leeds United, England), Adrian Leijer defender (Fulham Athletic, England), Trent McClenahan defender (Hereford United, England), Mark Milligan defender (uncontracted), Stuart Musialik midfielder (Sydney FC), Nikita Rukavytsya striker (Perth Glory), Kristian Sarkies midfielder (Adelaide United), Matthew Spiranovic defender (FC Nurnberg, Germany), Nikolai Topor-Stanley defender (Perth Glory), James Troisi midfielder (uncontracted), Tando Velaphi goalkeeper (Perth Glory), Ruben Zadkovich defender (Derby County, England), David Carney midfielder (Sheffield United, England) overage player, Jade North defender (Newcastle Jets) overage player, Archie Thompson striker (Melbourne Victory) overage player