Background and Objectives: The aim of the study was to determine the role and characteristics of nosocomial and community acquired Staphylococcus sepsis in admitted children in tertiary centers in Iran. Patients and Methods: A cross sectional descriptive-analytic study was performed since March 2008 to March 2009 in which all blood cultures from various admitted patients were checked for Staphylococcu aurues in Aliasghar Children Hospital, Tehran, Iran. Upon diagnosis by appropriate microbiologic tests, antimicrobial testing was done according to CLSI methods. Results: Overall, 2647 blood culture samples from 5197 admitted children were sent from which, 25 cases of S. aurues septicemia were isolated; the rate was 4.8 in 1000 admissions;1.3 in 1000 admissions were nosocomial and 3.5 in 1000 admissions were community acquired sepsis. Ten cases were neonates and remainder was older. Eighteen cases were CA and 28% were NI septicemia with mean age of 38.8 months and 8.2 months, respectively. Mean duration of admission in NI group was 20.5 days, however it was 12.6 days in CA group; they also had higher mortality rate. Conclusion: The rate of Staphylococcus sepsis in this study was higher than developed countries for both CA and NI cases, both groups had high rate of resistance. Although most cases were CA in which significant proportion had underlying malignancy, NI group had a longer duration of admission and mortality.