Xi told Lee Hae-chan, representing new South Korean President Moon Jae-in, that his visit showed the importance Moon attached to relations with Beijing.
"China, too, pays great attention to the bilateral ties," Xi said in comments in front of reporters in the Great Hall of the People in Beijing.
"We're willing to work with South Korea to preserve the hard-won results, properly handle disputes, put China-South Korea relations back onto a normal track and benefit both peoples on the basis of mutual understanding and mutual respect," he said.
Lee gave Xi a hand-written letter from Moon.
"President Moon said he hopes I'd also pass on his gratitude to you for your message of congratulation and the telephone call after he was elected," Lee said before reporters were asked to leave the room.
China has been infuriated by the U.S. deployment of an advanced Terminal High Altitude Area Defense (THAAD) anti-missile system in South Korea, saying it was a threat to its security and would do nothing to ease tensions with Pyongyang.
The United States and South Korea have said the deployment is aimed purely at defending against any threat from North Korea, which experts have thought for months is preparing for its sixth nuclear test in defiance of United Nations sanctions.
South Korea has complained that some of its companies doing business in China have faced discrimination in retaliation for the THAAD deployment.