The aims of this work were to compare and investigate the characteristics of the sausages and characteristics of traditional Turkish fermented sausage sold in the Istanbul market. Thirty various sausage samples (sucuk) labeled as fermented sausage (sucuk) in Istanbul market were collected in this study. The total mesophilic aerobic microorganisms, coliforms, lactic acid bacteria, Staphylococci and Micrococci, yeasts and molds were investigated at all samples. Also, the pH value, moisture, fat and protein content and sensory properties were examined. According to the sensory, physicochemical and microbiological findings, 8 samples (26.6%) of the 30 sausage samples have given similar properties with fermented sausages, 9 samples (30.0%) showed semi-fermented properties and 13 samples (43.3%) had the heat-treated non-fermented sausages properties. These results demonstrated that nearly 22 samples (73.3%) labelled as fermented sausages placed on the market were not fully fermented. Thus, these samples were included into the category of imitated and adulterated products in terms of related regulations.