A new antibiotic, named kinamycin1'2), has been isolated from the fermentation broth of Streptomyces murayamaensis sp. nov. Hata et Ohtani, which was obtained from a soil sample collected in Murayama, Saitama-ken, Japan. Kinamycins, produced as components A, B, C, and D as a mixture, are quinone antibiotics which show strong inhibitory activities against grampositive bacteria. Details of the fermentation, isolation, and physico-chemical and biological characteristics are given.In a previous communication1), characteristics of the new antibiotic complex, kinamycins A, B, G and D, were reported briefly. The present paper reports the fermentation, isolation, purification, and properties of the four components.