Septicemia continues to be an important cause of morbidity and mortality in the neonatal units and periodic review of cases to assess any changing trends in the infecting organisms and their antimicrobial susceptibility is important. Over a period of one year (July 2000 to June 2001), 632 samples of blood cultures were submitted to the bacteriology laboratory Microbiology, Lady Hardinge Medical College. These samples were investigated for microbial etiology and the isolates obtained were tested for their susceptibility to the commonly used antibiotics. Twenty per cent (125) cases were culture positive. Gram-negative bacteria were the predominant isolates (62%), commonest being Klebsiella pneumoniae (34%) followed by E. coli (17%), Acinetobacter spp. (9%) and Enterobacter aerogenes (2%). Gram-positive cocci were isolated in 20% cases, of which coagulase negative staphylococcus was the predominant isolate (11%) followed by Enterococcus spp. (5%) and S. aureus (4%). Candida spp. was isolated from 18% of cases. Resistance to commonly used antibiotics was seen in more than 35% of isolates. An alarming observation was the very high incidence of resistance to amoxycillin+clavulanic acid and ceftriaxone (>80%). All isolates showed highest susceptibility to ciprofloxacin.