The Shuangdun site is a typical cultural site of the middle Neolithic Age in Huai River, and a large number of ancient black potteries were excavated at the site. In this investigation many experimental means including XRD, Raman spectrum, refiring experiment, microstructure and petrographical analysis, SEM-EDS and so on were used. Based on these results, it was concluded that the pottery carbonization technique existed at the Shuangdun site. Meanwhile, part of potteries had been painted with a red pottery coating besides having carbonization inside, which made them unusual. -- ICCROM