Background: Staphylococcus aureus (S. aureus) colonization in health care workers (HCWs) is a major factor of nosocomial infections. Methicillin resistant S. aureus (MRSA) is incriminated in hospital-acquired infection. Objectives: To evaluate the colonization rates of nasal carriage of S. aureus and MRSA among HCWs at Al-Ahrar Teaching Hospital. Methods: We recruited 163 HCWs in a cross section study. S. aureus was identified phenotypically by coagulase, with DNase tests and genotypically by nuc gene detection. Antibiotics sensitivity was tested by disk diffusion. PCR for mecA was done to confirm MRSA identification. Results: Forty-eight S. aureus strain were isolated. The frequency of nasal colonization of S. aureus in HCWs was 29.44% (48/163), the frequency of MRSA isolates in HCWs was 27.6% (45/163), and frequency of MRSA isolates among S.aureus isolates was 93.8% (45/48). Prior infection (last 3 months) and living in crowded places increased significantly risk of MRSA nasal carriage by 29.3 and 79.59 folds respectively Conclusion: We demonstrated high rates of nasal carriage of S. aureus and MRSA among HCWs. Prior infection and living in crowded places were risk factors for methicillin resistance among isolated S.aureus stains.