Australia is buying 58 new F-35 fighter jets worth $11.5 billion, making a total of 72 jets owned by the government.
The government will also spend more than A$1.6bn on new facilities at two air bases in the states of New South Wales and the Northern Territory, according to BBC.
"I want to stress that this is money that has been put aside by government over the past decade or so to ensure that this purchase can responsibly be made," Prime Minister Tony Abbott said.
The F-35, also known as the Joint Strike Fighter (JSF), is built by Lockheed Martin Corp. It has been designed to avoid being detected by radar, making it a key asset to have while trying to penetrate enemy defences.
In 2009, Australia ordered its first batch of 14 F-35 jets. The first of those aircraft are scheduled to enter service in 2020.