Top Australian and American business leaders will be among the guests dining with Scott Morrison and Donald Trump at the White House.
The prime minister flew out of Canberra on Thursday morning for a state dinner and top-level meetings in Washington DC.
A slew of Australian business leaders will join the pair for dinner at the White House, including billionaire Andrew "Twiggy" Forrest, Kerry Stokes, Anthony Pratt and Gina Rinehart.
Golfer Greg Norman, Telstra chief Andy Penn, News Corp boss Rupert Murdoch and his son Lachlan Murdoch are also expected to be there.
Mr Morrison will focus on deepening the security cooperation between Australia and the United States, particularly in the Indo-Pacific, and on encouraging more trade and investment.
"We are an alliance partner that the United States knows they can rely on, a partner that pulls their weight in the alliance," he said.
In the days leading up to his trip, Labor has urged the prime minister to remind Mr Trump about the collateral damage being caused by the US-China trade war.
Labor deputy leader Richard Marles says any continuing trade tension is not good for Australia and Mr Morrison must make this case strongly to Mr Trump.
"But at the end of the day the prime minister is going to be judged on what outcomes he achieves and what he brings back," he said.
The US is pulling out all stops for the visit.
The state banquet is just Mr Trump's second in honour of a foreign leader during the three years of his term.
Mr Trump - well known for loving a winner - applauded Mr Morrison's surprise election win when they dined together on the eve of the G20 in Japan in June.
The week-long trip will take the prime minister to Washington DC, Chicago, New York and Wapakoneta, Ohio.
He will have a one-on-one meeting with Mr Trump in the Oval Office for what is bound to be a wide-ranging discussion, as well as meetings with US cabinet members and intelligence and security officials.
In New York, Mr Morrison will address the UN General Assembly and attend several functions, including with New Zealand Prime Minister Jacinda Ardern, looking at strategic responses to terrorists and violent extremists.
Foreign Minister Marise Payne told parliament the prime minister would use the UN speech to outline Australia's "national values and principles".
Australian Associated Press