In recent years, the resistance of staphylococci to may antibiotics is believed to be increase. We here present data on the prevalence of such resistance among 172 strains of staphylococcus aureus encountered at Department of Pediatrics of National Medical Center from 1973 to 1977. Since the resistant degree of the sensitive aorganisms to a certain antibiotics is chiefly dependent upon to difference in number and species of strains of micro-organism and their future management of staphylococcal infections. The results are summarized as follows: in the future management of staphylococcal infections. The results are summarized as follows: 1.The sex ratio between male and female was 1.3:1 with male preponderance. Most of the patient were distributed in newborn and infancy. 2. The mean number of annual isolated incidence was 34 to 35 cases. 3. The over-all incidence of mixed infection are 11.0% of the total strains isolated. 4. Overall incidence of antibiotic sensitivities of 172 strains of staphylococcus aureus are: Leu 97.6%, Cefa 97.5%, Meth 95.1%, GM 90.9%, Clox 73.2%, Doxy 67.6%, SM 56.2%, CM 51.7%, EM 47.3%, Carb 36.3%, TC 24.6%, PC 20.7%, respectively. 5. Sites of isolation of 172 strains of staphylococcus aureus strains studied are : throat 32.5%, Pus from wound or abscess 28.6%, umbilicus 22.6%, blood 5.8%, eye 5.2%, ear 2.9%, joint and pleura 1.2%, respectively.