Australian Olympic swimmer Ian Thorpe is in hospital battling a post-surgery infection.

The five-time gold medallist contracted the infection following an operation on his shoulder and he is now under the care of doctors at a hospital in Sydney, Australia who are treating his condition with antibiotics.

Thorpe's manager James Erskine confirmed the news to Abc.net.au, and dismissed reports suggesting the swimmer has been admitted to an intensive care unit.

The 31 year old checked into a rehabilitation centre earlier this year (14) to seek help in his long battle with depression.

He missed out on qualifying for the 2014 Commonwealth Games in Scotland due to a shoulder injury.