Botulism is a rare but severe disease. Whereas until 1980, only one case of botulism had been reported in our department, in 1999, a real botulism epidemic took place in Morocco. To our knowledge, it's the first outbreak of that kind in Morocco. We report here an epidemiologic and descriptive study of 11 patients suffering from botulism, admitted at the Infectious Diseases department and in the Medical Intensive Care Unit of Ibn Rochd University Hospital, from August, the 10th to October, the 1st, 1999. Clinical diagnosis of botulism was made, at the admission, on ocular signs (diplopia, ptosis), swallowing troubles and/or muscle weakness. There was no fever, no trouble of conscience and normal reflexes, at the early stage of the disease. The average age of patients was of 23.9 years +/- 12.07. Three patients were first admitted in the Medical Intensive Care Unit. The period before symptom appearance varied between 7 and 96 hours. Dysphagia sore throat, dry mouth and dysphonia were always found in all patients, with normal conscience. The fever was noted in 3 cases, polypnea in 3 cases leading to respiratory assistance in 2 cases. Neurologic findings were dominated by ptosis and hypotonia. The search of botulism toxin B in blood was positive in 6 cases. The electromyography showed clear signs of botulism. The evolution was favourable in 10 cases. Respiratory complications were found in 2 cases and infectious complications in 4 cases. One patient died. The period of hospitalization varied between 10 to 24 days with an average stay of 15.8 days. Eating "mortadella" has been noticed in 7 patients) and investigations permitted to identify the factory of "mortadella" as well as the toxin's type B responsible for these poisoning. It appears clearly that it is important to reinforce hygiene controls. Physicians and specialists in public health must be aware of the severity of this illness, knowing that the recovery is shortened when the treatment is administered on an early stage of the disease.