Japan's PM Shinzo Abe has said he has "great confidence" in US President-elect Donald Trump and he believes they can build a relationship of trust.
Mr Abe described the 90-minute meeting in Trump Tower, New York, as "candid", with a "warm atmosphere".
Some of Mr Trump's campaign rhetoric cast doubt over long-standing US alliances, including with Japan.
The meeting was Mr Trump's first face-to-face with a world leader since winning the presidential election.
The US and Japan have been key allies since the end of World War Two, when the US helped Japan rebuild its economy.
The president-elect has vowed to scrap the Trans-Pacific Partnership trade deal, that Mr Abe strenuously supports as a means of countering China's growing economic strength.
The deal was approved by the Japanese parliament, despite the likelihood that the deal will be cancelled when Mr Trump takes office.