China's ruling Communist Party will hold a key meeting from October 24 to October 27, the official Xinhua news agency said on Tuesday.
The session is likely to focus on revising rules of party discipline as President Xi Jinping keeps up a battle on corruption.
Formally called plenums, such meetings are typically held annually as the party's most important event and tend to map out major policies for the years ahead.
The October gathering is likely to be the final plenum before the party holds its five-yearly congress, expected in the autumn of 2017, where Xi will cement his power and possibly anoint a successor.
Xinhua announced the dates of the "sixth plenary session of the 18th Communist Party of China Central Committee"
without giving further details, though in July it said the secretive meeting would focus on amending rules for supervision in the party.
Since assuming power almost four years ago, Xi has waged an ambitious campaign against corruption, in which dozens of senior officials have been jailed, including the powerful former domestic security chief Zhou Yongkang.
At last year's meeting the party announced a landmark easing of family planning restrictions, to allow all couples to have two children, after decades of a strict one-child policy.