The highlight of Hu Jintao's four-day trip will be a summit on Thursday with George Bush, the US president.
But he first landed in Seattle, where he was to tour a production plant belonging to Boeing, the aeroplane company whose business has boomed on Chinese orders.
Hu, whose entourage includes his foreign and trade ministers, was also due to dine at the $100 million home of Bill Gates, the chairman of Microsoft and the world's richest man.
In Seattle's Chinatown, many shops hung Chinese and US flags to welcome Hu, but police also expected Falun Gong protesters to make their presence felt.
The group, which promotes spiritual meditation, has been officially banned in China since 1999.
Ahead of the visit, China sought to quell US trade complaints by signing contracts worth $16.2 billion when Wu Yi, the vice-premier, visited the US last week.
The state-run China Daily said in an editorial: "Hu's trip is set to clear US minds of doubts and suspicion about China.
But Robert Zoellick, the US deputy secretary of state, said Beijing had been "agonisingly slow" in meeting US demands to reform its currency.
The US says China still benefits
from an undervalued yuan
US officials say the yuan is undervalued, making Chinese exports artificially cheap.
Hu is seeking to calm US audiences not only about trade, but also about China's long-range ambitions.
In Seattle, Hu is to meet US and Chinese academics, including Zheng Bijian, a long-time Chinese Communist Party adviser who has promoted the idea that China's "peaceful rise" need not provoke severe conflict with Washington.
In Washington DC, Hu will have lunch at the White House, although not the state banquet China has pressed for. China describes Hu's trip as a fully fledged state visit but the White House has said it is not.
Analysts in both countries have said the White House meeting is unlikely to produce major breakthroughs on trade and diplomatic strains, which include differing approaches to the nuclear ambitions of Iran and North Korea.
"I intend of course to bring the subject up of Iranian ambitions to have a nuclear weapon with Hu Jintao"
Bush said he would raise the Iranian issue.
"I intend of course to bring the subject up of Iranian ambitions to have a nuclear weapon with Hu Jintao this Thursday," he said. "We'll continue to work diplomatically to get this problem solved."
Bush has singled out the $202 billion US trade deficit with China as his sorest point.
And he plans to press Hu to do more to stamp out commercial piracy of US patents, brands and copyrights. He has said he wants China to loosen currency controls faster to help balance trade flows.
But Chinese officials have said recently that their country must move at its own pace and will not be pushed by Washington into sudden currency and trade changes.
Wu, the vice-premier, said it was unscientific to blame China alone for the bilateral trade gap.
Hu wants to ensure stable relations with Washington as he prepares for his party's congress in 2007 and then Beijing's 2008 Olympics, Chinese academics and diplomats said.
He also wants Bush to offer some assurance that the US will give no leeway to Chen Shui-bian, Taiwan's president, Chinese analysts said.
Beijing says the self-ruled island must accept reunification with the mainland after over half a century of separation.
After his visit to the capital, Hu will go to Yale University to give a speech on China's "peaceful development".