Cervical necrotizing fasciitis is a rare but well known life-threatening soft tissue infection primarily affecting the superficial and deep cervial fascial planes. It may rapidly spread into the mediastinum along fascial planes. So, if proper diagnosis and prompt surgical debridement is delayed, the infection may cause descending necrotizing mediastinitis with extensive necrosis of overlying skin, destroying fascia and muscle. Therefore, the key to the successful outcome is early recognition and rapid initiation of definitive radical debridement. The authors report, along with a literature review, a case of cervical necrotizing fasciitis with atypical spreading into the lateral chest wall.