Reports said there were no suspicious circumstances surrounding his death.
Bannister made the final of the world championships in Daegu, South Korea, and the Beijing Olympics.
The news shattered the Australian track and field community, in which the charismatic Bannister was a popular team member.
"RIP Jarrod Bannister. A talented athlete with so much more to give. You will be missed," Australia's dual world and Olympic hurdles champion Sally Pearson said on social media.
Jarrod's mark of 89.02m is the current Australian record in javelin, set in Brisbane in 2008.
"On behalf of Athletics Australia, I extend our deepest condolences to Jarrod's family and friends and urge the athletics fraternity to support each other at this difficult time," said chief executive Darren Gocher.
Bannister in 2013 was controversially banned for 20 months for missing drug tests.
The national record holder missed three tests within 18 months, which is treated the same as a positive test.
Bannister blamed poor communication and procedures by Athletics Australia as a factor behind the circumstances that saw him breach the ASADA Athlete Whereabouts programme, which requires the drug agencies to be informed of the movements of athletes at all times.
In recent months Bannister had returned to serious training with a view to reigniting his career.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)