A UN source was quoted as saying Ban's trip could serve as a breakthrough in standoff over North Korea's nuclear weapons program.
UN Secretary-General Ban Ki-moon will visit Pyongyang this week for a possible meeting with leader Kim Jong Un, a South Korean news report said.
Yonhap news agency cited an unidentified source in the UN when it reported Sunday about Ban's Pyongyang trip. It gave no details on the purpose of the trip or the day it would take place.
UN spokesman Stephane Dujarric and Seoul's Unification Ministry said they had no comment.
If the trip does take place, Ban would be the first UN head to visit North Korea since Boutros Boutros-Ghali in 1993.
Yonhap, quoting another unidentified UN source, said Ban is expected to meet Kim because it's unlikely for the secretary general to visit a UN member state without meeting the country's leader.
That source was quoted as saying Ban's trip could serve as a breakthrough in the standoff over North Korea's nuclear weapons program and strained ties between the two Koreas. Ban was South Korea's foreign minister before taking up the top UN job.
International nuclear disarmament talks remain stalled since early 2009 and experts believe North Korea has since built a small and growing atomic bomb arsenal and advanced its missile program. Hundreds of thousands of combat troops from the two Koreas face each other along the world's most heavily fortified border since their war in the early 1950s ended with an armistice, and not a peace treaty.