A novel strain, 219820(T), whose metabolites were found to be active against tumour cells, was isolated and characterized. The isolate belonged to the genus Streptomyces and had white to grey aerial mycelium and long chains of smooth spores in the aerial mycelium. A phylogenetic tree based on 16S rRNA gene sequences showed that strain 219820(T) had highest similarity to members of the genus Streptomyces and was most closely, albeit loosely, associated with Streptomyces crystallinus NBRC 15401(T) (98.624 % similarity), Streptomyces melanogenes NBRC 12890(T) (98.565 %) and Streptomyces noboritoensis NBRC 13065(T) (98.564 %). However, DNA-DNA relatedness and phenotypic data readily distinguished strain 219820(T) from these phylogenetically related type strains. It is evident from the combination of genotypic and phenotypic data that strain 219820(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces sanyensis sp. nov. is proposed; the type strain is 219820(T) ( = CGMCC 4.5626(T) = DSM 42014(T)).