"Kim Jong-un, chairman of the Workers' Party of Korea and Chairman of the State Affairs Commission of the Democratic People's Republic of Korea (DPRK) visits China from June 19 to 20", Xinhua said.
Besides being the U.S.'s largest trading partner, China is arguably the most important player in Trump's "maximum pressure" campaign to force Kim to give up his nuclear arsenal.
Kim praised China's "important role in protecting the Korean Peninsula's peace and stability", state-run CCTV said.
Trump and Kim pledged in a joint summit statement to "work toward the complete denuclearisation of the Korean Peninsula".
Following the historic US-North Korea summit in Singapore a week ago, China suggested the UN Security Council could consider easing the economic restrictions on its Cold War-era ally.
The visit shows that China is "key" to the talks, Wang said.
The visit is the North Korean autocrat's third to China since March, when he made his inaugural foreign trip as leader.
In a news conference following the summit, Trump said North Korea had agreed to return the remains of U.S. soldiers.
The first ladies of North Korea and China joined their husbands Kim Jong-un and Xi Jinping at the gathering
The outing comes as China has sought to strengthen its role as a mediator between the United States and North Korea, where Beijing claims compelling security and economic interests.
Officials here say his visit was expected to crystallise the next course of action by him to announce the denuclearisation process and further steps on the Korean peninsula. This approach advances the US objective of achieving a diplomatic solution in the Korean Peninsula, where available military options would cost the lives of hundreds of thousands of innocent civilians and could lead to a nuclear war. Pompeo would go on to make security assurances to North Korea and wave before them the prospect of U.S. investment in exchange for denuclearizing, which has yet to materialize.
Trump in the past has said Kim has changed his mind after his talks with Xi.
Such measures would fit neatly into China's own gameplan for decreasing tensions in the region-a "freeze for freeze" formula that has called for the United States to cease joint-military exercises in return for North Korea stopping all nuclear tests, resulting in a more peaceful peninsula with reduced American influence while also bringing into question the commitment of the USA to its Asian allies.
"No matter the changes in the global and regional situation, China's party and government's resolute position on being dedicated to consolidating and developing Sino-North Korea relations will not change", the report cited Xi as saying. For its part, China has been warning of strong retaliation.
Analysts saw the summit outcome as a sign of China's influence.
"There remains hard work" and "difficult days" in denuclearisation negotiations with North Korea, Pompeo had said.
"Our government hopes China will play a constructive role in resolving this problem", ministry spokesman Noh Kyu-deok told a regular briefing.