In this article, we report on two cases of gas-forming necrotising fasciitis of the neck admitted to our university hospital. In both patients, large gas-forming abscesses were detected by CT scan. Microbiologic smears revealed a mixed flora of aerobic and anaerobic bacteria, predominantly anaerobic streptococci. Emergency surgery with debridement and drainage, appropriate antibiotic therapy, and intensive care were performed. One 58-year-old patient with no concommittent disease recovered well after fourteen days. The other 71-year-old patient with diabetes mellitus and renal insufficiency died despite adequate therapy as a result of metabolic disturbances.