Cervical necrotizing fasciitis (CNF) is a rare but well-known, rapidly fulminant polymicrobial infection of subcutaneous tissues. It is characterized by progressive destruction of fascia and adipose tissue, with sparing of the overlying skin and muscle in the initial stage. CNF may rapidly spread into the thorax along fascial planes, and the associated diagnostic delay makes this descending necrotizing mediastinitis,the most lethal form of mediastinitis, with a mortality of approximately 40 per cent. So aggressive multidisciplinary therapy with surgical drainage is mandatory. We present three cases of descending necrotizing mediastinitis with literature review.