Trump announced at a White House press conference that US Space Force General Michael Guetlein would be the lead program manager for what the president said would be a $US175 billion ($A273 billion) project.
Golden Dome will "protect our homeland," Trump said from the Oval Office and added that Canada had said it wanted to be part of it.
The office of Prime Minister Mark Carney was not immediately available for comment.
First ordered by Trump in January, Golden Dome aims to create a network of satellites to detect, track and potentially intercept incoming missiles.
The shield could deploy hundreds of satellites for missile detection and tracking.
It will take years to implement as the program faces both political scrutiny and funding uncertainty.
Democratic lawmakers have voiced concern about the procurement process and the involvement of Trump ally Elon Musk's SpaceX, which has emerged as a frontrunner alongside Palantir and Anduril to build key components of the system.
The Golden Dome idea was inspired by Israel's land-based Iron Dome defence shield that protects it from missiles and rockets.
Trump's Golden Dome is much more extensive and includes a massive array of surveillance satellites and a separate fleet of attacking satellites that would shoot down offensive missiles soon after lift-off.
Tuesday's announcement kicks off the Pentagon's effort to test and ultimately buy the missiles, systems, sensors and satellites that will make up the Golden Dome.
Trump, who said the project would be completed by the end of his term in January 2029, said Alaska will be a big part of the program and named Florida, Georgia and Indiana as also benefiting from the project.
The project's funding remains uncertain.
Republican lawmakers have proposed a $US25 billion initial investment for Golden Dome as part of a broader $US150 billion military package but this funding is tied to a contentious reconciliation bill that faces significant hurdles in Congress.
"Unless reconciliation passes, the funds for Golden Dome may not materialise," said an industry executive following the program.
"This puts the entire project timeline in jeopardy."
