Cervical necrotizing fasciitis (CNF) is an uncommon, yet clinically significant infection that rapidly progresses to involve the deep neck spaces. Early recognition and aggressive surgical intervention and debridement are important, as this disease is associated with a high morbidity and mortality. In this report, we present a case of CNF and descending mediastinitis from a non-odontogenic source in a patient presenting with neck swelling and odynophagia.