Abstract: Background and Objective: Poisoning by carbon monoxide (CO) is the leading cause of poisoning deaths in the world. In Morocco, it remains a common, serious and often unrecognized and constitutes a public health problem. The present study aimed to describe the main epidemiological and clinical characteristics of occurred cases and to determine factors that may have influenced the evolution of these cases. Materials and Methods: This is a prospective study on CO poisoning cases occurred in Fez city between January, 2009 and December, 2016. Data were retrieved from medical records of patients who were received at the emergency department at Ibn Alkhatib hospital. The data were analyzed using Statistical Package for Social Sciences. Results: About 2163 cases of intoxication were recruited. Of which 1806 cases are intoxicated by CO (83.5%). The mean age was 25.4±16.1 years, the sex ratio = 0.44 in favor of the female sex (69.44%). Poisoning was accidental in 100% of cases. The oxycarbon poisoning was seasonal. The main cause is the malfunctioning of gas-fired water heaters and the use of braziers. According to the source of the cases, poisoning mainly affects disadvantaged areas (76.94%), poisonings were of urban origin in 99.1%. The group of adults was the most exposed (52.49%) cases, followed by the adolescent group (15-19 years) (25.75%). The age of children (5-14 years) have accounted for 21.1% of all cases, which requires awareness of parents to the dangers of carbon monoxide poisoning (42.47% of cases are collective). It was essentially isolated poisoning (57.53%) that occurred at place of residence in 97.95% of cases. Clinical manifestations are dominated by neurological signs (42.36%), followed by digestive signs (34%), respiratory signs (22.82%) and cardiovascular manifestations (0.35%). Poisoning was relatively benign (98.78%). Treatment based mainly on oxygen therapy normobar. Conclusion: Oxycarbon poisoning remains underestimated. Therefore it was concluded that prevention is an indispensable element.