In a White House interview, broadcast on Thursday night, the US president said Mr Rudd was a good operator in multilateral forums.
"Kevin is somebody who I probably share as much of a world view as any world leader out there. I find him smart, but humble," he told ABC TV.
"He works wonderfully well in multilateral settings.
"He's always constructive, incisive. And you know, I think he is, like me, a pragmatic person."
Asked about Afghanistan, Mr Obama acknowledged the 11 Australian soldiers who have been killed in the US-led war since 2002.
Obama pays tribute to Aussie troops
"Australia has made enormous sacrifices and an enormous investment both on the military side and on the civilian side, they've been a very strong partner and America is grateful for that," he said.
Afghan President Hamid Karzai has reportedly said he would join the Taliban if more pressure was placed on him.
But Mr Obama had more diplomatic words, describing the leader of the war-torn nation as a proud man with a strong sense of Afghan nationalism.
"Well, I think that President Karzai is capable of leading his country into the 21st century and stabilising it," he said.
'The war is improving'
He rejected assertions the war situation was not improving ahead of a US troop reduction beginning in mid-2011, and acknowledged he was in regular contact with Mr Rudd about Australia's military commitment.
"We can't be in there in perpetuity," he said.
"Neither the American people nor the Australian people should be asked to carry that burden any longer than it needs to be carried."
US still strong: Obama
Mr Obama played down the prospect of China one day overtaking the United States as the world's largest economy, adding his nation would be number one for a "very, very long time".
"The Chinese standard of living and industrial output per capita is about where the United States was back in 1910, I mean they've got a lot of catching up to do."
On climate change, Mr Obama pointed out that the US and Australia had, per capita, some of the world's biggest carbon footprints.
But he said Mr Rudd had played a "critical" role at the ultimately-doomed UN climate change summit in Copenhagen last year.
Australia visit still on the cards
Mr Obama said his wife Michelle and their daughters Sasha and Malia wished to visit Sydney and Canberra during their stay, likely to be over two days.
He recalled visiting Australia during his childhood in Indonesia.
"I used to travel through Australia when my mother was living in Indonesia and my grandparents were living in Hawaii," he said.
"We'd usually go through Sydney and memories I have, not only of it being a beautiful country but of people being just wonderfully hospitable and kind to me, are ones that I carry with me."
With Australian Treasurer Wayne Swan due to fly to Washington on April 22 for the next Group of 20 summit of finance ministers, Mr Obama said the US was co-ordinating with Australia to make sure financial market reforms took place not just on Wall Street but also London and Hong Kong.