The reaction of benzoylation of bleomycetin, a glycopeptide antibiotic, and its cuprum complex was studied with the chloranhydride and carbodiimide methods. Acylation of the antibiotic cuprum complex by an equivalent quantity of benzoyl chloride resulted in formation of a mixture of mono- and disubstituted derivatives while with the use of a 3-fold excess of chloranhydride it was possible to obtain dibenzoylbleomycetin as a sole reaction product. Interaction of the bleomycetin cuprum complex with activated benzoic ether resulted in formation of a product monosubstituted by the antibiotic spermidine fragment. After acylation of the free antibiotic by the carbodiimide and chloranhydride methods tri- and tetrabenzoyl derivatives of bleomycetin were isolated respectively.