Abstract: OBJECTIVE To understand the drug resistance and molecular typing of methicillin-resistant Staphylococcus aureus (MRSA) in clinical and environmental specimens from Intensive Care Unit (ICU) of 12 Grade III Class A hospitals in Inner Mongolia Autonomous Region. METHODS MRSA strains were collected from patients and environmental samples in ICU of 12 hospitals from Jan. to May 2018 for drug resistance analysis and pulsed field gel electrophoresis (PFGE) typing. RESULTS A total of 47 strains of MRSA were detected from the patients in the 12 ICUs, of which 22 (46.81%) were from sputum, 14 (29.79%) were from blood and 11 (23.40%) were from others. No resistance of MRSA to tigacycline, vancomycin, furantoin and linezolid was found. The resistance rates of MRSA strains to quinoluprine/dapeptin and compound xinomine were 2.17% and 14.89%, while the resistance rates for other antibiotics were all above 70%. A total of 11 MRSA strains were isolated from the environment in ICU, 3 strains were detected in the bed fence, 2 strains were detected on the surface of the bed ends and the treatment table respectively, and 1 strain each was detected from other sites. A total of 41 MRSA strains were preserved from the patients and the environment in ICU. PFGE homology analysis showed that there were 17 (A-Q) types by cluster analysis, with no obvious dominant type. The type of MRSA with largest number was type L with 7 strains (17.07%), followed by type H (5 strains), type Q (4 strains), type K (3 strains), and the remaining types only contained 1-2 strains. CONCLUSION The PFGE cluster analysis of MRSA showed that the same MRSA was detected from the patients and their surroundings. The control system of nosocomial infection should be strictly enforced, the infected patients should be isolated, and the sanitation and disinfection of the environment should be strengthened to avoid the outbreak of infection.