Aster atropurpurea W.P. Li & G.X. Chen, a new species of Asteraceae from Hunan Province (China), is described and illustrated. Morphological, molecular and cytological data were used to assess its taxonomic status and phylogenetic relationships. Morphologically, A. atropurpurea is most similar to A. saxicola, but differs from it by having strigose stems and middle leaves, green phyllaries (apex), 3–7(12) capitula, and the lamina of the ray florets 2.1–2.4 mm broader. Phylogenetic analysis based on the nuclear ITS and ETS regions provided good support for recognizing A. atropurpurea at the specific level, phylogenetically closely related to A. homochlamydeus and A. handelii. Aster atropurpurea is octaploid and its karyotype is 2n = 8x = 72 = 8M + 56m + 8sm, which distinguishes it from morphologically similar species.