As well, special forces soldiers will provide specialised training to state and territory police forces and some may be embedded to improve co-operation.
In certain circumstances, the military could take charge of responses.
The changes, unveiled by Prime Minister Malcolm Turnbull, follow a review into the deadly 2014 Lindt Cafe siege.
Justice Minister Michael Keenan says the changes build on an already strong relationship between the military and police, with police to retain the lead as first responders.
‘But there will be certain circumstances where the Australian Defence Force might be useful,’ he told reporters on the Gold Coast.
‘When that is the case, I think Australians would understand we need arrangements that will allow that to happen.’
Ultimately, the final call about bringing in the military is with the Commonwealth, Mr Keenan said.
Defence Industry Minister Christopher Pyne refused to be drawn on what might have happened had the changes been in place before Sydney’s Lindt cafe siege in December 2014 which resulted in the deaths of two hostages.
‘It would be quite wrong of me to start trying to re-open the issues around the the Lindt Cafe,’ he said.