The visit has raised speculation that it could include an announcement about the dormant six-nation nuclear disarmament talks.
South Korea's Yonhap news agency quoted diplomatic sources in Beijing as saying China, North Korea's closest ally, would not be sending such a high profile visitor unless it had won some assurance from Pyongyang that could ease tension over the current nuclear standoff.
Earlier this month, Kim Jong-il, the North Korean leader, told a visiting Chinese envoy that he would work towards denuclearisation through multilateral talks.
In recent months, the reclusive communist state has reached out to the international community after being hit with a tightening of UN sanctions over a nuclear test in May.
However, the six-nation nuclear disarmament talks have been stalled since North Korea pulled out of the process in April after UN criticism of its long-range missile tests.
The talks bring together negotiators from US, China, Japan and Russia and the two Koreas.
Last month, Washington said it was prepared to hold direct talks with Pyongyang in order to bring it back into the six-party framework.
The US had previously said it would only sit down with North Korean officials for talks that included the six-party partners.
Talks on Pyonyang's nuclear programme have unfolded in fits and starts, with North Korea taking some steps to disable its nuclear facilities after agreeing an aid-for-disarmament deal in September 2005.
However, it has carried two nuclear tests since, first in 2006 and then in May this year.
Despite condemnation from the UN Security Council, the North followed its May nuclear test with several further missile tests, ratcheting up tension with Japan and South Korea.