The purpose of this monocentric prospective cohort study was to assess mortality in intensive care unit (ICU) patients requiring more than 6 hours of mechanical ventilation (MV) in a developing country. The study setting was a 10-bed polyvalent ICU at the Centre Hospitalier Régiona1 in El Maarouf, Comoros Islands. The study population included a total of 106 patients requiring MV out of 633 consecutive patients admitted to the ICU over a 10-month period. Study parameters included demographic data, simplified acute physiology score version 2 (SAPS II), reason for admission, urgency of MV, duration of MV, complications of MV need for sedation and mortality in hospital and at one year. In-hospital mortality was 59%. Mortality was significantly higher in patients presenting elevated SAPS II and requiring myorelaxant drugs. Age, gender, reason of admission, emergency, sedation, complications of MV, duration of MV were not correlated with mortality. The best prognosis was associated with the following indications: severe malaria, meningitis, eclampsia and poisoning. All patients who left the ICU (41) were alive at one year. Mortality associated with use of MV for resuscitation in a developing country was similar to that observed in developed countries. The young age of patients, acute nature of manifestations and reversibility of diseases encountered may explain the favorable outcome observed in this study. The initial diagnosis and associated risk factors (using a severity score if necessary) must be taken into account in deciding the indication for starting and stopping MV. The results of this study show that MV is feasible and effective in a developing country, but requires experience, inventiveness and realism.