OBJECTIVE To investigate the characteristic of multidrug resistant organisms(MDROs) in hospital or community-acquired infection,so that it can approach effective infection management.METHODS Patients infected by Staphylococcus,Enterococcus,Escherichia coli,Klpneumoniae and A.baumanni were investigated in a Hospital from June 2008 to May 2009.RESULTS Among total 929 strains of bacilli from patients,367 were MDROs infection,the detection rate of MDROs,CA-MDROs or HA-MDROs was 39.5%,35.6% and 51.4% respectioety infection;The detection rate of MDROs from HAI patients was significantly higher than that from CAI patients(?2=19.2 P=0.00).There were differences between HA-MDROs and CA-MDROs in different departments.MRSA,ESBLs-kp And PDR-AB were isolated mostly from sputum of patients,and ESBLs E.coli mostly from urine of CAI patients.CONCLUSIONS It is important to analyze the characteristic of HA-MDROs or CA-MDROs in the treatment of infection or use of antibiotics from experience.MDROs control is full of difficulties as a result of high CA-MDROs rates.