Leptospirosis, a common form of zoonosis, especially in rainy, countries, is caused by Leptospira interrogans. In our region of Turkey this type of disease has often been encountered in connection with rice harvesting and we therefore attempted to evaluate the prevalence of L. interrogans in wild rats in our region. Fifty-nine Rattus norvegicus rats were trapped alive in different areas of an approximate to100 km stretch of seashore in the Middle Black Sea region of Turkey. L. interrogans was determined by PCR in sera, kidney and brain tissue. Sixteen (27.1%) kidney samples and 10 brain tissue samples (16.9%) were positive for L. interrogans. No PCR positivity was seen in sera samples. Five sera were positive by microagglutination test. A large proportion of wild rats in our region were found to be carriers of L. interrogans. We conclude that people who are exposed to rat urine in their daily life are at risk of acquiring L. interrogans.