Air Force One landed in Tokyo on Saturday, the start of a four-day visit for Mr. Trump and first lady Melania Trump.
Trump is speaking at a reception with Japanese and American business leaders at the USA ambassador's residence in Tokyo after arriving in the country.
During remarks to business leaders on Saturday night, Mr Trump ribbed Japan over its trading edge while saying progress had been made.
His comments underscored the competing dynamics of a state visit created to show off the long US-Japan alliance and the close friendship between Mr Trump and Japanese Prime Minister Shinzo Abe even as trade tensions run high.
On Monday, Mr Trump will become the first head of state to meet Emperor Naruhito since he ascended to the throne this month. Trump will also present the victor of Tokyo's spring sumo wrestling tournament a trophy after taking in a few rounds from ringside seats, an engagement that White House officials say he's been anticipating eagerly.
President Trump is in Japan for the next several days for what amounts to mostly being a ceremonial visit rather than a substantive one.
US Trade Representative Robert Lighthizer held talks with his Japanese counterpart, Economy Minister Toshimitsu Motegi on the sidelines of the visit. But that's highly unlikely given the two sides are still figuring out the parameters of what they will negotiate.
He says the US and Japan "are hard at work" negotiating a bilateral trade agreement, but is pointing to the gap.
Later they attended a dinner with Japanese business leaders meant to promote investment in the United States - fueled along, Trump hopes, by a new trade agreement that reduces the $68 billion trade deficit with Japan. "And we're getting closer", he said, while urging the business leaders to invest more in the U.S.
"The Japanese public recognizes how critical the U.S. -Japan alliance is and, somewhat in contrast to our Western European allies or Canada, Japan lives right next door to China and North Korea, has very little room for friction with the United States", Green said.
Trump, the first American president to participate in such a ceremony, said later it was an "incredible evening".
Japan's Emperor Naruhito, and his Harvard-educated wife, Empress Masako, will host an imperial state banquet for Trump.
U.S. President Donald Trump on Sunday presented a special trophy to the victor of the sumo tournament in Tokyo.
Trump landed from his overnight flight shortly after a magnitude 5.1 natural disaster struck just south of Tokyo and rattled the city. Mr Trump was to arrive two hours later. The agency said there was no danger of a tsunami from the inland quake.
Mr Trump watched in awe as the wrestlers took to the ring, performing ritual exercises before the tournament commenced.
Hours before Trump's arrival Saturday at Haneda International Airport, National Security Adviser John Bolton told reporters at the U.S. Embassy in Tokyo that North Korea will be among the first issues that Trump and Abe discuss.
The Trump administration has been threatening Japan with new tariffs on imports of autos and auto parts on national security grounds. He tweeted that the tests weren't a concern for him - even though they most certainly are for Japan, due to the country's proximity to the North. Japan is deeply dependent on the US for security, and Abe has tried to encourage Trump to maintain global agreements and keep pressure on North Korea. That raised alarm bells in Japan, where short-range missiles pose a serious threat.
At the golf course, Trump ignored a shouted question from a United States reporter about whether he believed North Korea had violated UN Security Council resolutions.
"The president will likely meet again with relatives of Japanese citizens who were abducted by North Korea in the 1970s and '80s", Szechenyi said.