The clinical efficacy of enoxacin (ENX) was evaluated in 39 patients having chronic prostatitis. The overall clinical efficacy of ENX was determined by three factors, (1) the effect on bacteria, (2) white blood cells in the VB3 and (3) the subjective symptoms. The overall clinical effectiveness rate was 80%. ENX eliminated 66.7% of the bacteria in the VB3. As determined from white blood cells in the VB3, 56.4% of patients were relieved of the inflammation of prostate by ENX. The subjective symptoms were improved by ENX treatment in 77% of the patients.