The new damselfly family Shundeagrionidae is proposed for Shundeagrion cheni n. gen. n. sp. from the Paleocene of the Sanshui Basin, South China. This new family is unique in a combination of wing venation characters that are separately encountered in other extant and fossil groups. Together with the extinct groups Dysagrionidae, Sieblosiidae, Whetwhetaksidae, Menatlestidae, Latibasaliidae, Euarchistigmatinae, and Eodysagrioninae, the Shundeagrionidae n. fam. is the eighth major group of Paleogene damselflies with large wings, very long postnodal area, and nodus relatively basally recessed. It confirms that an important diversification occurred worldwide among the damselflies during the Paleocene and Eocene. These relatively ancient groups were progressively replaced by the modern families of large calopterygoid damselflies during the Oligocene and the Miocene, leading to the modern faunas.UUID: http://zoobank.org/e18cf9dc-c438-484c-b97e-dcc6d63986bd