Attorney-General George Brandis says Australia faces a new threat from citizens with terrorist experience who have returned home after fighting in the conflict in Syria.
At the inaugural Interpol Global Security and Counter Terrorism Convention in Sydney on Tuesday, Senator Brandis said terrorism continued "to be a global threat of the first magnitude".
"We know that the threat of an attack here on Australian soil is real," he said.
Mr Brandis said Australia was facing a new threat from citizens who had returned home after fighting in the conflict in Syria.
"We are witnessing a growing trend of citizens travelling offshore to engage in and support terrorist activities and conflict and it has been brought home to Australia most particularly by the Syrian conflict," he said.
"These individuals are not only potentially in breach of Australian laws and commit offences offshore, but upon their return to Australia they may pose significant threats to our national security."
He said Australian fighters who returned from Syria could be "radicalised and obtain new skills", potentially including those needed to carry out an attack on Australian soil.
AAP reports 200 law enforcement officers from 60 countries are attending the conference.