Methicillin-resistant Staphylococcus aureus (MRSA) has evolved as one of the most important causes of hospital infections worldwide. Screening for carriage of (MRSA) is fundamental to modern-day nosocomial infection control. Effective decolonization decreases the risk of subsequent staphylococcal infection and controls the spread of MRSA. The aim of this study was to identity the frequency of MRSA nasal carriage among health care workers in Assiut University Hospitals and to determine the efficacy of combined local mupirocin ointment and oral rifampin and trimethoprim /sulfamethoxazole for nasal MRSA decolonization for implementing various infection control policies to control the spread of MRSA in our Hospitals. Swabs were taken from the anterior nares of the 150 health care workers in different departments in Assiut University Hospitals, Egypt. Identification of Staphylococcus aureus was done by the conventional bacteriological methods. Methicillin resistance was detected by growth on oxacillin resistance screening agar base (ORSAB). For those who showed nasal carriage of MRSA, topical application of mupirocin & oral treatment with rifampin and trimethoprim/sulfamethoxazole were administered for 5 days. Screening was carried out 48 hours, 1 month, 6 months and 9 months after the treatment cycle was completed. Out of 150 health care workers, 45.3% (68) were MRSA carriers. Post treatment screening showed a reduction in the number of carriers. After 48hs post treatment, they were 11.8%, followed by 1.5% after 1month. Recolonization occurred at 6 and 9 months post treatment (23.5% and 14.7% respectively) but were still less than before treatment. We conclude that we have a high percentage of MRSA nasal colonization among the studied health care workers. A single treatment cycle of combined local mupirocin, oral rifampin and trimethoprim/sulfamethoxazole resulted in successful MRSA decolonization in the early post treatment period (within 1 month) with no documented adverse effects. However, nasal MRSA recolonization occurred again in the late post treatment period (>= 6months). Screening and treatment should be made an essential protocol to decrease the number of carriers transmitting MRSA to the hospital settings. [Enas A Daef, Nahla M Elsherbiny, Maggie A Ibrahim and Entsar H Ahmed. Decolonization of Methicillin Resistant Staphylococcus areus Nasal Carriage Among Health Care Workers. Life Sci J 2012; 9(4):4496-4501]. (ISSN: 1097-8135). http://www.lifesciencesite.com. 676