A new species in the genus Phytodietus Gravenhorst, 1829, P. xui Kostro-Ambroziak Reshchikov sp. n. is described from the Yunnan Province of China. An identification key for the eight species of Phytodietus currently recorded in Mainland China is provided. P. longicauda (Uchida, 1931) is recorded for the first time in China and P. spinipes (Cameron, 1905) is recorded in Guangdong and Hunan Provinces.
Keywords: China, Ichneumonidae, Phytodietus, Tryphoninae, Yunnan, Hymenoptera.