Michael Clarke will captain Australia in Tuesday's Twenty20 international against New Zealand.
Ricky Ponting is being rested, giving the opportunity for Clarke, 26, to lead his country for the first time.
The New South Wales batsman admitted his surprise at the decision to make him skipper ahead of more experienced candidates Adam Gilchrist and Michael Hussey.
"It certainly was a shock to me. I was a little bit speechless," said Clarke.
"It's any young kid's dream to captain their country.
"This is a great opportunity but there is no doubt Ricky is our leader and will be for a lot longer yet. I'm certainly proud and honoured to be given this opportunity."
Chairman of selectors Andrew Hilditch said the choice of Clarke was made with an eye on the future.
"We have taken the opportunity to enhance the leadership skills of Michael Clarke to assure the long history of strong leadership of Australian cricket is continued into the future," read a statement from Hilditch.
Ponting and opening batsman Matthew Hayden are both rested for the match in Perth on December 11.
Australia's 12-man squad includes all-rounders Ashley Noffke and Adam Voges, while Shaun Tait has overcome an elbow injury and cpuld make his first international appearance since April's World Cup final.
Australia Twenty20 squad: Michael Clarke (captain), Adam Gilchrist, Andrew Symonds, Michael Hussey, Brad Hodge, Adam Voges, Ashley Noffke, Brett Lee, Nathan Bracken, Stuart Clark, Mitchell Johnson, Shaun Tait