The three-month amnesty will allow people to hand in unregistered guns from July 1.
Government said the amnesty - where people can hand in their guns, no questions asked - was being held against a backdrop of an increased threat of terrorism and ongoing gun violence.
"What we want to do is reduce the number of guns like that in the community", he said.
In an earlier statement, he said "We are living in a time when our national security environment has deteriorated".
As a response to the horrific bloodshed, John Howard - who was Prime Minister at the time - introduced a national amnesty and tougher gun laws.
Illegal guns were used in recent terrorist activity such as a deadly shootout in Melbourne this month, and the 2014 Sydney cafe siege which left two hostages dead.
"We are always pleased to see the states, territories and Federal Government taking steps to get illegal guns off our streets", she said.
While individual states periodically run amnesties, this is the first national one since 35 people died at the historic Tasmanian colonial convict site of Port Arthur in 1996.
Australia, which has banned all semi-automatic rifles and all semi-automatic and pump-action shotguns, and as a restrictive system of licensing and ownership controls, has had no mass shootings since 1996.
There were 47 violent crimes involving firearms across Australia in 2013, the previous year for which statistics are available, according to the Australian Institute of Criminology.
Although Australia's gun controls have been very effective, reducing the risk of being killed by shooting in this country by 50 per cent since the mid-1990s, a spate of terror incidents and the ambush-style murder of a Queensland police officer have sparked fresh public concerns. They were not handed in during the buyback and there are no records that they even exist, the report said.
It said guns can be bought easily in the United States and sent to "countries such as Australia with relative anonymity, especially where transactions are made using emerging technologies and business practices, such as the darknet and freight-forwarding services".
Those caught outside that period face fines of up to A$280,000 ($212,730; £166,480) or up to 14 years in prison.