Facial cellulite are infections of the cellulo-adipose tissues of the human face. Head and neck cellulitis is today one of the most serious ENT emergencies, which is very life-threatening and requires immediate multidisciplinary care. Diabetes mellitus is one of the most common predisposing factors. They are serious conditions because of the rapidity with which they tend to spread. They perform an extensive necrotizing condition, developing from a banal, pharyngeal or dental infection, and spreading along the aponeurotic partitions of the face and neck. The etiologies are diverse and come mainly from dental infections. Nasosinus infections can be the cause especially on immunocompromised patients. The diagnosis is mainly clinical. The treatment is medico-surgical and must start as soon as the diagnosis is made to avoid complications. We report a case of an abscess of the nasal septum responsible for facial cellulitis in 45-year-old diabetic patient. Her diabetes was irregularly followed. The septal abscess spread over a few days to the tissues of the face. He was received in a picture of impaired general condition with significant facial oedema. He received rapid and appropriate medical and surgical car. He progressed well under treatment after 15 days.