In leptospirosis, severe pulmonary hemorrhagic syndrome has replaced Weil's disease as the main cause of mortality, with rates of up to 75%. Four men, all farmers, were admitted to the intensive care unit between August 2009 and July 2010 with a diagnosis of acute respiratory distress syndrome. All patients presented with fever, hemoptysis, bilateral pulmonary infiltrates in chest radiographs, and thrombocytopenia and had compatible epidemiological history with leptospirosis; 3 patients had anemia, 3 had renal failure, 2 had increased creatine kinase, whereas bilirubin was slightly increased in only 1 patient. Leptospirosis was diagnosed serologically in all cases. Empirical therapy with ceftriaxone was administered immediately to all patients, while implementation of ARDSnet protective mechanical ventilation approach combined with an early goal-directed hemodynamic approach led to a relatively low mortality rate (25%). Acute Physiology and Chronic Health Evaluation II, Simplified Acute Physiology Score II and Sepsis-Related Organ Failure Assessment scoring systems were unable to predict the outcome of the patients with leptospirosis-associated severe pulmonary hemorrhagic syndrome.