Schleck, awarded the 2010 Tour de France yellow jersey after the disqualification of Spain's Alberto Contador for doping, said he was looking forward to the challenge after missing most of the European season due to injury.
"I'm very excited to go South Australia," he said. "I've heard about the race from other riders many times, and I'm very excited to see what it's like to race in Australia."
Race director Mike Turtur said the course should suit the Luxembourg climbing specialist, who rides for the RadioShack Nissan team and has done well in hilly classics.
"Next year the race will feature a number of challenging ascents, and I'm sure all fans look forward to seeing Schleck tackle climbs such as Corkscrew Road and Old Willunga Hill," said Turtur.
"After a challenging season this year, I'm sure Andy will be eager to stamp his authority on the 2013 cycling calendar."
The 27-year-old missed much of year with a fractured pelvis.
The Tour Down Under is held in Adelaide and regional South Australia from January 20-27.