The study was under taken to detect mecA gene of methicillin resistant Staphylococcus aureus (MRSA) by PCR. It was carried out in the department of Microbiology, Mymensingh Medical College in collaboration with the Department of Medicine under the Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh between the periods from July 2006 to June 2007. A total of 40 S. aureus strains were used in this study. Isolates of S. aureus were identified by standard microbiology technique and their antimicrobial susceptibility test was done by disk diffusion method according to NCCLS. Minimum inhibitory concentration (MIC) of oxacillin was determined for all isolates by standard agar plate dilution method. All strains were tested for mecA gene by PCR. Out of 40 S. aureus strains 15(37.5%) were detected as MRSA by disk diffusion and agar dilution method but 10(25%) yielded mecA gene by PCR. Detection rate of MRSA by disk diffusion and agar dilution test showed significant difference to that by PCR (p<0.001).