Pyongyang is on a charm offensive accompanying the sudden diplomatic rapprochement on the peninsula, with a summit due later this month between leader Kim Jong Un and the South's President Moon Jae-in.
In its report Sunday, the Korean Central News Agency (KCNA) did not specify what Kim discussed with the Chinese diplomat, Song Tao, but Kim was reportedly "pleased" with the recent improvement of Pyongyang-Beijing relations and expressed hope that ties would improve further.
North Korea's relationship with its sole ally during the 1950-1953 Korean war had strained when China pushed United Nations to punish Pyongyang for its nuclear weapons programme.
North Korea is marking its biggest national holiday by playing up its intention to strengthen ties with China.
Song is heading a delegation that arrived in Pyongyang on Friday which includes an art troupe taking part in the April Spring Friendship Art Festival. Song, head of the International Department in the Communist Party's Central Committee, reportedly replied that it was the Chinese government and Communist Party's "firm policy" to work toward improving relations between both countries.
"He said with deep emotion that the Chinese comrades accorded cordial hospitality to him with utmost sincerity in token of warm comradely friendship during his recent unforgettable visit to China", the KCNA said.
Footage broadcast on Chinese state television on Sunday evening showed Kim greeting Song with a warm hug and the pair later dining in a large hall adorned with a giant picture of Kim and Xi together last month.
Song Young-gil, who heads the Presidential Committee on Northern Economic Cooperation, met officials from the Chinese Academy of Social Sciences and the Charhar Institute, the committee said.
China is North Korea's strongest economic and military ally, but their relationship cooled after Beijing joined sanctions previous year.
When nuclear-armed North Korea put on a flower show previous year to celebrate the birthday of its founder Kim Il Sung, scale model rockets were on display.