Secretary of State John Kerry arrived in Beijing for the annual China-US dialogue.
Chinese President Xi Jinping called for mutual respect between the two nations, saying a confrontation with the United States would be a “catastrophe”.
Diplomats are expected to discuss China’s currency, North Korea and tensions in the South China Sea.
The US delegation is led by John Kerry, who said in his opening remarks that the United States did not seek to “contain” China.
Xi Jinping said the interests of the two countries are now “more interconnected than ever” and much can be gained from co-operation.
“The China-US confrontation between the two countries and the world would definitely be a disaster.” he said.
“We must respect each other and treat each other equally and respect the sovereignty and territorial integrity of the other and respect the choice of the other on the path of development.”
John Kerry, meanwhile, said the United States was “not seeking to contain China” and urged Beijing not to “interpret this as a comprehensive strategy” when the United States differs from China on certain issues.
President Barack Obama also said in a statement that the United States “welcomes the emergence of a stable, peaceful and prosperous China.”
“We remain committed to ensuring that cooperation determines the overall relationship,” he said.
US leaders have also called on China to contribute to maintaining stability in Asia.
John Kerry said the United States welcomed China, which “contributes to the stability and development of the region and chooses to play a responsible role in world affairs.”
Negotiations are coming with China, which has been embroiled in fierce disputes with several neighbors in the region, notably Vietnam and the Philippines, over claims in the South China Sea.
The United States, for its part, has stepped up joint military exercises with the Philippines and its military presence there, a move that has raised concerns. One of the latest exercises took place in the South China Sea near disputed waters two weeks ago.
Increased anti-Japanese rhetoric has also come from China in recent weeks, following a decision by the Japanese cabinet to reinterpret the constitution, giving the Japanese military more freedom to fight abroad.
Both sides say there are a number of islands in the East China Sea and ties are strained.
The United States and China have also had differences in recent months, especially over cyberattacks.
In May, US authorities accused five Chinese military officers of hacking into US business. Beijing has vigorously denied the allegations, accusing the United States of launching cyberattacks against China.