Euphorbia xiangxiui, a new species of Euphorbiaceae from Eastern China, supported by morphological and molecular evidence, is illustrated and described here. It can be distinguished from its closest relatives by the combination of several characters, including taller stature (up to 1.6 m), leaves of 5‐18 × 0.6‐3 cm in size, color of primary involucral leaves and cyathophylls changing from pink to rose, fading to green after fruiting, and four to six reniform-rounded concave glands. The molecular phylogenetic analysis, based on combined nuclear ribosomal ITS and plastid ndhF sequences, further supports that E. xiangxiui should be placed in the East Asian Clade of Euphorbia subg. Esula sect. Helioscopia.

Keywords: Euphorbia xiangxiui; Flora of China; leafy spurges; phylogeny; taxonomy