ObjectiveTo realize the status and causes of catheterassociated nosocomial infection (CANI) in surgical intensive care unit (SICU) , so as to decrease the incidence by taking proper measures.MethodsSix hundred and fifteen patients with catheters  in SICU between  2005 and 2009 were  monitored prospectively,  including the occurrence of CANI, patients’ age, length of hospital stay, invasive procedures, and pathogens.ResultsOne hundred and ninetyseven of 615 patients (32.03%) developed CANI,  and CANI rate was 2.60%,12.85% and 56.40% in patients with 1 kind , 2  or 3 kinds of catheters simultaneously respectively, there were significant difference among three groups (χ2=151.55,P<0.001). The rate of ventilatorassociated pneumonia (VAP), catheterassociated urinary tract infection (CAUTI) , and  central venous catheter (CVC)associated bloodstream infection (CVCBSI) per 1 000 catheter days was 15.51, 13.70 and 5.79 respectively. The average catheter  utilization days before the occurrence of CANI were as follows:  ventilator (12.22±11.29) days, urinary catheter (13.09±13.29) days , CVC (20.64±18.39) days respectively. The major pathogen in  VAP , CAUTI and  CVCBSI  was Acinetobacter spp.(18.80%), Candida albicans (36.46%) and Acinetobacter spp.(18.75%) respectively.ConclusionPatients with more catheters , long hospital stay and long duration of catheters are prone to develop nosocomial infection . The key to the prevention of emerging of drugresistant strain and decrease in NI are strengthening of  disinfection and isolation, shortening  the time of catheter  retaining, implementing hand hygiene, and using antimicrobial drug rationally.