Abstract: OBJECTIVE To further understand the current statue of prevalence of nosocomial infections caused by multidrug-resistant organisms (MDROs) in malignant tumor patients so as to provide scientific basis for prevention and control of harms to the malignant tumor patients.METHODS A total of 1 538 malignant tumor patients who were treated in the hospital from Jan 2014 to Jan 2016 were enrolled in the study, the patients with MDROs infections were screened out, the drug susceptibility testing was performed, and the risk factors were analyzed.RESULTS Of the 1 538 malignant tumor patients, totally 60 had the MDROs infections, with the infection rate of3.9%.A total of 98 strains of drug-resistant pathogens were isolated from the specimens of the 60 patients with MDROs infection, of which 67 (68.3%) were gram-negative bacteria.The isolation rates of ESBLs-producing Escherichia coli and Klebsiella pneumoniae were 94.7% and 86.7%, respectively.There were 31 (31.6%) strains of gram-positive bacteria, and the isolation rates of MRSA and MRCNS were 66.7% and 72.7%, respectively.The drug susceptibility rates of the drug-resistant strains were relatively low, and all of the gram-negative bacteria, except for Acinetobacter baumannii and Stenotrophomonas maltophilia, were only susceptible to imipenem.All of the gram-positive bacteria showed extremely high resistance to cephalosporins, meanwhile, 1 strain of vancomycin-resistant Enterococcus was isolated.The major risk factors for the MDROs infections included age, complication with hypertension, diabetic mellitus, disturbance of consciousness, invasive operations, and length of hospital stay.CONCLUSIONThe MDROs infection is a leading cause of death of the malignant tumor patients or even an immediate cause of death, therefore, it is of great significance to investigate the risk factors for the MDROs infections in the malignant tumor patients and analyze the result of drug susceptibility testing so as to reduce the infection rate and the rate of death due to the infections.