The leaders are expected to focus on cooperation on North Korea's nuclear threats and ways to normalize their ties strained by a year-long feud over Seoul's decision to allow for deployment of a USA missile defense system.
"The leaders shared the view on the need to stably manage the current security situation on the Korean peninsula in a stable way and agreed to peacefully resolve the North Korean nuclear issue through dialogue".
Last month, the two countries' foreign ministry officials agreed to return to "a normal development track", mending relations that have been frayed since the decision by Seoul and Washington in July 2016 to deploy a Thaad battery in Korea to defend against North Korea.
Earlier, the South Korean government proposed no additional THAAD deployment in the Korean peninsula, non-participation in the missile defense system of the United States, and no joint military drill with the US and Japan.
"At the end of the meeting, President Xi said this is a meeting that marks a fresh start of relations between Japan and China".
In response, Li said it would be "difficult to avoid some concrete and sensitive issues as China-South Korean relations develop", but added that the "prospects for practical cooperation by China and South Korea are very bright".
It was Moon's first meeting with the Chinese premier since he took office.
Summit chairman Philippine President Rodrigo Duterte, speaking ahead of Moon, also highlighted the "growing ties" of the regional bloc and South Korea in the past 28 years, calling the two parties "partners for peace and prosperity".
By agreeing on Moon's visit to Beijing in December, the first step is now seen as having been achieved. It is the second summit since the meeting in Germany in July, and the first of its kind since the agreement on the improvement of the bilateral relations on October 31.
Xi urged South Korea to take a "responsible attitude on THAAD that stands the test of history", Xinhua said.
Russian Prime Minister Dmitry Medvedev is going to attend the 12th East Asia Summit in Manila on the final day of his three-day visit to the Philippines.
South Korean President Moon Jae-in holds a summit with Chinese Premier Li Keqiang at the Sofitel Hotel in Manila, Philippines on November 13.