A total of 80 Streptomyces strains were isolated from major potato growing areas of Iran including, Hamedan, Esfahan, Khorasan and Chahar Mahal-e Bakhtiary provinces during 2000. Forty six representative Streptomyces strains were selected and their morphological and physiological features determined. The strains were grouped by numerical analysis of their phenotipic features. Five phena were differentiated. The first phenon was identified as S. scabies. The second cluster of the strains was similar to S. turgidiscabies and also to a lesser extent to the causal agent of russet scab. Some characteristics of the third and fourth clusters of the strains including spiral spore chain, gray mass spore color on YMEA and melanin production from tyrosine were similar to S. scabies but others were similar to S. europeaiscabies and S. stelliscabies and in the last one being similar to S. acidiscabies. This is the first report for S. scabies from Iran. In host range studies the representative strains were pathogenic on potato (Solanum tuberosum), radish (Raphanus sativus), bean (Phaseolus vulgaris) and beet (Beta vulgaris). Tested strains were reisolated from artificially infected but symptomless corn (Zea maus), tomato (Lycopercicum esculentum), carrot (Daucus carota), Ientis (Lense sp.), eggplant (Solanum melongena) and Amaranthus sp. Plants but not from the inoculated wheat (Triticum aestivum), barley (Hordeum vulgaris), rape seed (Brassica napus) or alfalfa (Medicago sativa) plants under greenhouse conditions.