NW-G01, a novel cyclic hexadepsipeptide antibiotic, was isolated by macroporous resin and silica gel column chromatography and HPLC from the fermentation broth of strain no. 313. The producing strain was identified as Streptomyces alboflavus on the basis of the morphological characteristics, physiological property and 16S rDNA gene sequence analysis. NW-G01 exhibited strong antibacterial activity against Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, methicillin-resistant S. aureus, and their MIC values were 3.90, 3.90, 7.81 and 7.81 microg ml(-1), respectively.