Few data are available about severe malaria in Madagascar. Our aims were to describe epidemiological, clinical and therapeutic aspects of severe malaria in patients in Antananarivo. We conducted a retrospective study from 1 March 2006 to 31 March 2008 at the infectious disease department. We recorded 61 cases of severe malaria among 1,803 in patients. Sex ratio was 2 and average age was 35.3 years old. Three pregnant women were recorded among women (15.8%). Self-medication was registered in 23%. Among 35 patients who received first medical care, no one had parasitological examination. The treatment was inadequate for all patients (n = 19). Conscience impairment (65.6%), jaundice (24.6%), seizure (18%) and prostration (14.8%) were the major severe signs. Diagnosis was made 6.54 days after the onset of the disease. Mortality rate was 11.5%. Self-medication, inappropriate primary care and delayed diagnosis represented risk factors for severe malaria in our cohort.