Xi's plane left Pyongyang's Sunan International Airport in the afternoon. He had arrived in Pyongyang early Thursday, becoming the first Chinese head of state to visit the North in 14 years, reports Yonhap News Agency.
Xi and North Korean leader Kim Jong-un held summit talks on Thursday at which the Chinese leader said he will help address the North's security concerns, and Kim said he will exercise patience in efforts to resolve the Korean Peninsula issue, according to their state media reports.
It marked their fifth summit since last year and came after they last met in Beijing in January.
Late Thursday, Xi and his wife, Peng Liyuan, along with Kim and his wife, Ri Sol-ju, watched a group gymnastics performance together at Pyongyang's May Day Stadium.
Details on his schedules on Friday have yet to be confirmed. Xi was expected to pay a visit to the Friendship Tower, a symbolic monument commemorating China's participation in the Korean War in support of the North.
During Thursday's summit, Xi voiced support for the "political" resolution of the Korean Peninsula issue and pledged to play a "positive" and "constructive" role in realizing the denuclearization of the peninsula, according to China's Xinhua news agency.
Kim said that the North will "stay patient" despite the lack of a positive response to Pyongyang's active efforts to ease tensions and expressed hope that the "relevant party" will work with North Korea to "seek solutions that accommodate each other's legitimate concerns and push for results from the dialogue process".
Thursday's summit came amid the drawn-out stalemate in denuclearization talks between Pyongyang and Washington following the February summit that ended without a deal.
( With inputs from IANS )