The aim of this study was to investigate a small tularemia outbreak in a village of Karamursel county of Kocaeli province (located in North-west part of Turkey), between 22 January - 8 March 2005 and to present the anti-epidemic measures implemented. Following diagnosis of oropharyngeal tularemia in two patients living in the same village, a field investigation was performed at this region. All patients have undergone physical examination. Blood samples and if possible throat swabs and lymph node aspirates were taken from the patients and water samples from the natural spring water suspected to be the source of the infection, were also taken. Cultures were performed from the clinical samples and filtrated water samples. Francisella tularensis antibodies were screened by microagglutination (MA) test in the serum samples of the patients. F.tularensis DNA was investigated in the filtrated water samples by real-time PCR assay. A total of 17 patients were diagnosed as tularemia with their clinical features and MA test results (>= 1/80). All the patients had oropharyngeal tularemia except one who had ulceroglandular form. The age range of the patients was 27-80 years (mean age: 48 +/- 17 years), and 10 (59%) were female. Weakness (100%), swelling on the neck (94%) and sore throat (88%) were the most common symptoms, whereas cervical lymphadenopathy (94%) was the most frequently seen clinical finding. F.tularensis could not be grown in the cultures, however F.tularensis DNA was detected in the samples of the natural spring water by real time PCR. The patients were treated with streptomycin, ciprofloxacin, or doxycycline, and all the patients have recovered. The outbreak was taken under control after cleaning the spring water tank and chlorination of the water.