BACKGROUND: The random amplified polymorphic DNA (RAPD) analysis was investigated to see if this method could be a useful tool for monitoring of epidemic outbreaks of methicillin-resistant Staphylococcus aureus (MRSA) among patients and healthcare workers (HCW) in the intensive care units (ICU). METHODS: Thirty-eight MRSA strains were isolated from patients and HCW in Dong-A University Hospital ICU from October, 1998 to December, 1998 (10 patients and 8 HCW) and May, 2001 to July, 2001 (15 patients and 5 HCW). All strains were typed according to antimicrobial susceptibility and RAPD analysis patterns. mecA genes were detected using polymerase chain reaction (PCR). RESULTS: Twenty one of 25 (84%) and 12 of 13 (92%) MRSA, isolated from patients and HCW, respectively, were mecA positive. mecA positive MRSA were classified into 18 different types by RAPD analysis. CONCLUSION: DNA fingerprinting using RAPD analysis is a simple, effective, and rapid method for discriminating MRSA strains, and may be applicable in detecting outbreaks of S. aureus infections in the ICU.