A new species of Ulocladium was isolated from diseased leaves from two Cucumis sp.growing in Sinkiang and Gansu provinces of China.Conidia were isolated from necrotic leaves and used to establish single-spore pure cultures.Conidia were harvested from cultures 7 d after incubation for morphological comparisons.The morphology of this species resembles that of U.botrytis and U.consortiale.However it is distinguished from these two species by the sizes of obovoid to broadly ellipsoidal conidia and longer conidiophores.A taxonomic description of U cantlous, comparison with related species in this genus, and a species phylogeny based on the partial nucleotide sequence of the glyceraldehyde-3-phosphate dehydrogenase (gpd) gene and the Alternaria alternata major allergen (Alta 1) gene are provided.