OBJECTIVE To find the cause of lower respiratory tract infection as soon as possible and take measures to control the infection.METHODS The records of hospitalized patients in the intensive care unit(ICU) form Nov 28 to Dec 6 in 2006 were analyzed;and the disinfection efficiency,sterilization effect and the environment were monitored.RESULTS The incidence rate of lower respiratory tract infection was 54.55%.The qualified rate of disinfection and sterilization monitoring was 35.71%.The respiratory tubing,bed handle,bottle openner,computer mouse,the surface of the file cabinet and air vents were heavily infected.The Staphylococcus aureus was isolated from the quilt cover and the surface of the file cabinet.CONCLUSIONS We should put more emphasis on the management of the infective disease in the ICU,on hand washing and the cleanliness and maintenance of the devices.Disinfection and isolation guidelines should be strictly followed to reduce the incident rate of infection in the ICU.