The man appears in the video posted on YouTube with his face blurred and can be seen preparing his suicide attack, the Sunday Morning Herald reported on Tuesday.
The report said he is believed to be the Brisbane man who carried out a suicide bombing in September at a school where Syrian government soldiers were based.
The man went under the name Abu Asma al-Australi.
Australian intelligence agencies say at least 200 Australians are involved in the war in Syria.
The video appears to have been posted by the terrorist al-Nusra Front, the al-Qaeda linked militia that has emerged as the most heinous group battling Syrian armed forces.
The video shows the truck bomb being given a final check, then the man farewelling his fellow terrorists.
It then shows from a distance the massive explosion and fireball created by the bomb, accompanied by the man's comrades.
The man is believed to have travelled to Syria around the middle of this year and sent his young family home to Australia before carrying out his attack.
In a recent report to the Australian Parliament, security agency ASIO said it was "concerned about the potential for Australians in Syria to be exposed further to extremist groups and their ideology".
"An individual who becomes involved in the conflict and who holds, or develops, an extremist ideology could return to Australia not only with the intent to facilitate attacks onshore but also with experience and skills in facilitating attacks," it said.
NTJ/BA