Six (6) strains of bacteria isolated from the Black Sea water and mollusks Mytilaster lineatus have been assigned to Shewanella genus on the basis of phenotypical and molecular-genetic study. Partial sequence of 16S rRNA gene revealed 100% similarity of three of these strains to S. baltica, although they had some phenotypical differences. Three more strains were genetically related to S. colwelliana and S. affinis (99-100% of 16S rRNA sequences similarity), but they differed from these species as well as from each other in some phenotypical properties, so the question about their taxonomic status still remains open. In aerobic conditions the Black Sea strains of S. baltica adsorbed significant quantities of Fe III from the media. They reduced it to Fe (II) in anaerobic conditions. Strains isolated from mollusks were not able to reduce Fe (III).