In this study, the microbiological quality and shelf-life of sausage treated with different concentrations of chitosan was investigated. Sausage samples obtained from a local producer were dipped into 0.25%, 0.5% and 1% chitosan solutions prepared with 1% acetic acid. The samples were drained, vacuum packed and stored at 4oC a period of sixty days. The sausages were evaluated for sensorial properties and microbiological counts (aerobic mesophilic bacteria, total psychrotrophic bacteria, lactic acid bacteria, molds and yeasts) on days 1, 5, 10, 15, 30 and 60 of storage. All samples vacuum packed were stored. All the three different chitosan application (0.25%, 0.5% and 1.0%) did not cause undesirable alteration in sensory properties of sausages. Even more, treated samples had a brighter color than the control group. The first alterations indicating the spoilage were observed at the 20t h storage day in the untreated samples (control group). However, an abnormal changes were not determined on the samples treated with chitosan, even on the last day of storage. The counts of all determined microbiological indicators were significantly affected by the treatment with chitosan (P<0.05). The results indicated that the application of chitosan on the sausage surface by dipping improves the microbiological quality and extends the shelf-life, which could an alternative to chemical protective additives.