Background & Objectives: Septicemia is one of the serious infections of neonatal period that its microbial etiologies bacterial causes are different in various parts of the world. Incidence of sepsis in developing countries is much more than that of developed countries and it is one of the important causes of mortality and morbidity in neonatal period. This study was done to determine the microbial etiology, mortality and resistance pattern of septicemia.

 Methods: This study was a retrospective cross-sectional study for three years on blood cultures of 210 neonate admitted in pediatric hospital in Tabriz. Demographic information, clinical findings, types of bacteria in blood culture and antibiogram were analyzed.

 Results: Mean age of patients was 8±2 days in which sixty percent were male and the rest were female. Among 12 isolated bacteria, negative staphylococcus coagulase was the most common. 68.6% of isolated bacteria were positive gram. 31.4% of negative gram were in which klebsiella pneumoniae had the most frequent incidence. 22.9% of neonates died, in which 9% of them weighed less than 1500 grams. Among 8 antibiotics used by disc diffusion method, ampicillin showed the highest (97.4%) and vancomycin the lowest (6.7%) resistance.

 Conclusion: septicemia is still the main problem in neonatal ward and neonatal intensive care unit. The etiologic agents and resistance pattern of each area should be considered in starting empirical treatment.