Tularemia caused by Francisella tularensis, which is considered a biological warfare agent, is a widely distributed zoonosis. In this study, we aimed to compare a 2005 outbreak of tularemia that was confirmed as waterborne by PCR to outbreak of tularemia that was reported as waterborne in 2000 and to investigate the changes of epidemiological characteristics between these two outbreaks occurring in the same region. In the present study, a total of 11 patients were diagnosed with tularemia. In the 2000 outbreak, oropharyngeal type was observed in 19 patients, and ulceroglandular type in 3 patients. In the 2005 outbreak, oropharyngeal type was observed in 8 patients, and oculoglandular type in 3 patients. However, our cases are not sufficient to make a conclusion that the characteristics of tularemia seem to be changing.