Background: Icterohemorrhagic form of leptospirosis has a high mortality rate. In this study, the clinical manifestations, epidemiologic and laboratory findings and outcome of Weil’s disease were investigated. Methods: A descriptive cross- sectional study was conducted on 66 consecutive patients with icterohemorrhagic leptospirosis who were admitted to Razi Hospital (The Therapeutic Center of Infectious Diseases in the North of Iran) in 2013. The inclusion criteria were as follows: All patients who had clinical and epidemiological data suggestive of leptospirosis and displayed icterohemorrhagic form at the time of admission or during hospitalization. All patients were visited on admission, one, two and six weeks later. Demographic data, clinical, laboratory features and complications were evaluated, and statistical analysis was performed using SPSS version 13.0. Results: Among 66 patients, 89.4% (n = 59) were male, 60% (n = 40) were farmers and 9.1% (n= 6) had a history of swimming in rivers. The most common complaints were fever and jaundice, respectively. The most common clinical symptoms were fever (90.9%), myalgia (75.8%), chills (70.8%) and headache (65.1%). Hyponatremia and hypernatremia were seen in 7.6% and 72.8% of the participants, respectively. Also, hypokalemia was observed in two patients (3%). Approximately, half of the cases had leukocytosis and 90% had thrombocytopenia. Rise of AST, ALT, ALP and bilirubin were seen in 95.2%, 93.6%, 76.2% and 100% of the patients, respectively. Of the patients, 42.4% experienced complications of icterohemorrhagic leptospirosis including acute renal failure (30.3%) pneumonia (25.8%), pancreatitis (4.5%), subarachnoid hemorrhage (1.5%) and gastrointestinal bleeding (1.5%). Three cases (4.5%) died, 42 cases (63.7%) were discharged with residual effects and 52 patients (78.8%) had positive serology. Conclusion: The most significant biochemical abnormalities were thrombocytopenia, hyperbilirubinemia, hyponatremia and hypernatremia and azotemia and the latter remained stable in 2% of the patients at least until the end of the 6-week period.