Runan Commandery (汝南郡) was a commandery of Yu Province lying south of the Ru River in what is now Henan and Anhui. It became famous for its concentration of learned gentry families, most notably the Yuan clan of Runan, whose members dominated Eastern Han officialdom and later produced warlords such as Yuan Shao and Yuan Shu.
The commandery also produced figures who later served Shu Han, including Chen Dao and Chen Zhi. Runan and its counties such as Pingyu appear frequently in the histories as the origin of scholars and officials.