Leptospirosis is a widespread infection throughout the world. We observed that case series and sporadic case presentations are more frequent in publications about leptospirosis, from our country. In this presentation, three cases with fever, myalgia and headache symptoms diagnosed as leptospirosis are reported. While the level of serum bilirubin in two of the cases was high, the clinical progress of the remaining case was hepatorenal syndrome (Weil's disease), which is a very serious clinical form. In the latter case, renal failure was accompanied by neurological symptoms and thrombocytopenia. The three cases had risk factors such as being a farmer or fisherman, which is significant for leptospirosis. Microscopic agglutination test (MAT) was used for their diagnosis. Antibody response to Leptospira interrogans serovar bratislava was observed in all of the three cases. In all cases, the patients were treated with oral doxycycline 100 mg bid, and all of the three were discharged from the hospital. In conclusion, a careful assessment of risk factors in the history of the patient will assist the diagnosis of leptospirosis, when evaluating patients with non-specific clinical and laboratory results. Early treatment is a very important factor influencing the course of the disease.