OBJECTIVE To introduce a new type of tracheal cannula which has the top hole and can seal the outlet for patient with severe brain injury after tracheotomy. METHODS Patients with severe brain injury after tracheotomy were divided into test group using the new type of tracheal cannula(25 cases) and control group using the cuffed Portex tube(25 cases).The incidence,the onset time and the time for control of pulmonary infection were compared between the two groups. RESULTS In the test group,the incidence of pulmonary infection was 52%(13 cases),the onset time was(3?1.3) days and the time for control was(5?1.7) days;in the control group,the above indices were 84%(21 cases),(3?1.5) days and(12?2.2) days separately. CONCLUSIONS The new type of tracheal cannula which has the top hole and can seal the outlrt is better than the cuffed Portex tube in the prevention and treatment of pulmonary infection after tracheotomy.