Australia will provide Canada with over-the-horizon radar technology in the largest defence export deal in the country's history.
The $2.5 billion agreement is the first time the Australian technology has been sold overseas.
The technology allows for a radar system to detect targets at a longer distance than traditional radars.
The deal was signed in Canberra on Monday between the two countries.
Canada's Secretary of State for Defence Procurement, Stephen Fuhr, said the deal formalised Canada and Australia's commitment to deeper co-operation in defence and security, critical minerals, artificial intelligence, energy, and investment.
"We've stood shoulder to shoulder for generations as the world adjusts to its new strategic and economic realities," Mr Fuhr told reporters in Canberra.
"I can't think of a stronger partner to work with more than Australia."