Abstract: OBJECTIVE To characterize the clinical infections and prevalence of methicillin-resistant Staphylococcus aureus (MRSA) for further controlling the spread of MRSA in hospitals. METHODS The detection rate,sources of specimen, distributions and infection sites of MRSA isolated from 266 765 cases of inpatients from 2012 to 2017 were studied. RESULTS A total of 673 strains of S. aureus were isolated and 292 MRSA strains were detected with a detection rate of 43.39%. There were 284 cases of nosocomial infections, of which community acquired-MRSA (CA-MRSA) infections accounted for 72.54% and hospital acquired-MRSA (HA-MRSA) infections accounted for 27.46%. Among all the HA-MRSA infections,the incidences of ventilator-associated pneumonia,surgical site infection,and catheter-related bloodstream infection were significantly higher than others,which accounted for 64.10% totally (50/78). The HA-MRSA infections mainly occurred in departments of intensive care, neurosurgery, orthopedics and kidney medicine. Secretions, sputum and blood were the most common specimens from which MRSA strains were isolated. CONCLUSION It is of great significance to actively execute epidemiological study of HA-MRSA for developing, implementing and assessing the prevention and control measures for nosocomial infections. The key emphasis in future work for preventing and controlling MRSA nosocomial infections should be focused on the effective implementation of prevention and control strategies aiming for high-risk departments, key sites and key populations.