Abstract: Antibiotic 799 was isolated from the culture fluid of Streptomyces 799. The physical and chemical characteristics of antibiotic 799 were compared with spiramycin produced by S. ambofaciens. Their UV, IR, MS and NMR (¹H and ¹³C) spectra were analysed. On the basis of above data it was concluded that although taxonomially Streptomyces 799 is distinct from S. ambofaciens, the antibiotic-799 and spiramycin produced by them are identical.