"They have set Barack Obama the mighty task of rebuilding the American economy and leading the recovery of the international economy: a great task for a man I believe to be a great man," Mr Rudd said.
"I believe from everything I have seen, read and heard and from the conversations that I have had with him that the American people have chosen well."
Mr Rudd says Australia will work side-by-side with Mr Obama to overcome the global financial crisis.
"These are dark times but a new age and a new optimism - tempered by the magnitude of the challenges ahead - is about to dawn across the Pacific," he said.
"Barack Obama truly is the hope of our time and I say this to the new President of the United States and through him to the new people, that Australia as always stands ready to work with America in the great challenges that lie ahead."