President Xi Jinping's visit will mark the first time for a Chinese leader to visit Seoul before Pyongyang -- a strategic move that's being seen as a stern warning against North Korea's nuclear threats.
Naturally, North Korea's nuclear program will top the agenda at Thursday's summit, where the two leaders are expected to issue a joint statement on the issue.
Strong words against North Korea's nuclear program will lump more pressure on the isolated regime,.. and mark a shift away from the traditionally closer ties between North Korea and China.
Against the backdrop of Japan's continued efforts to backtrack on its apologies for historical wrongdoings, Tokyo's recent attempts to whitewash history will also be up for discussion.
"It's only natural the two leaders talk about Japan. They'll discuss Japan's historical issues and its push to deny historical facts."
China has seen its relations with Japan sink to their lowest levels in recent years, from territorial disputes in the East China Sea over a group of islands, as well as Japan's move to undermine its 1993 apology for its wartime atrocities.
It's a similar story for Korea,.. but as it needs to maintain its strategic trilateral relations with the United States and Japan, attention is on whether the two will be able to issue a joint statement against Japan's recent moves.
China and Korea may make headway on the economic front though.
Observers say the two leaders will likely focus on their free trade agreement during the summit.
Considering the two countries are nearing the tail end of negotiations, there's growing expectation the FTA could be ready to go before the end of the year.
The two countries began negotiations back in 2012 and have held 11 rounds of talks since then.
Yoo Li-an, Arirang News.