Representatives of Streptomyces strains isolated from environmental soil samples were subjected to identify for the diagnostic characters recommended by Williams el of. (1983b) as a duplicate. Diagnostic characters were tested using a mixture of spores and mycelial fragments, respectively, in order to identify some Streptomyces species and strains on computer assited identification. Most of the marker strains were identified to tile correct clusters. In Contrast, 20 strains out of 38 unknown strains were assigned to any major cluster described by Williams et al. (1983a). Computer-assisted identification procedure has provided reliable identification scores for marker or unknown strains.