Two aminoglycoside antibiotics, destomycins A and B were isolated from a culture filtrate of Streptomyces rimofaciens1) and their structures were determined by the authors. We have found a new minor antibiotic named destomycin C in a crude powder of destomycins. In this communication, the isolation, characterization and structural study of destomycin C are presented. The structure has been elucidated by comparison of its carbon-13 spectrum with those of destomycins A and B.