Among the isolates of methicillin resistant Staphylococcus aureus (MRSA) which were isolated at Juntendo University Hospital between 1992 and 1998, there were 2 arbekacin resistant strains, 9 mupirocin resistant strain and 7 teicoplanin resistant strains. For each resistant strain, we studied pulsed-field gel electrophoresis (PFGE) pattern, coagulase type, antimicrobial susceptibility pattern and investigated a distribution of the resistant strains at the hospital wards. Two arbekacin resistant strains showed PFGE type A (A3 and A7, respectively). Nine mupirocin resistant strains were type C1; 3 strains, type A (A1, A4, A8); 3 strains and type D, E, G for 1 one each strain. The antimicrobial susceptibility pattern was not similar to each other and the strains were isolated from different year. It is suggested that these strains were not same origin. Seven teicoplanin resistant strains had PFGE type B (B1; 5 strains, B2/B5; 1 each strain). The antimicrobial susceptibility pattern of the strains was similar to each other and the strains were isolated from the same hospital ward between 1995 and 1997. From the above fact, the resistant strains appear to be hospital strains which have same origin.