Abstract： Objective To explore the diagnosis and treatment of descending necrotizing mediastinitis (DNM). Methods We retrospectively analyzed the records of eight DNM patients treated at Tangdu Hospital between 2006 and 2009 year. There were 7 males and 1 female aged from 21-98 years with a median age of 49.5 years. The diagnostic criteria included clinical manifestations, neck and chest CT scans, and bacteriological culture. Six of the patients had odontogenic infections and six had diabetes. Antibiotic treatment, incision drainage, and other symptomatic treatments were applied. Two patients received cervical incision drainage, five received thoracotomy, and one received video-assisted thoracoscopic surgery (VATS). Results After treatment, six patients recovered and two died of heart failure and neck vessel rupture. According to the bacterial culture, six patients presented mixed infections, and four of these presented mixed aerobic and anaerobic infections. The mean operation time was 75.6 minutes, the average volume of pus removed during the operation was 318.7 ml, and the average inpatient stay was 18 days. At six months follow-up, all six surviving patients showed improvements in quality of life. Conclusion The valid diagnosed criteria of DNM include history, sign, symptom, neck and chest CT scanning, and secretion culture.DNM mortality can be reduced by employing broad spectrum antibiotics early in treatment, individual surgical managements, and effective treatments for complicating illnesses.