This study examines the antibiotic susceptibility of 1792 bacterial strains isolated from hospitalized children between January and December 1993. A total of 1015 Gram-negative rods represented by members of Enterobacteriaceae family (770) and nonfermenters (245) were isolated. The most resistant strains were noticed among Klebsiella pneumoniae and Enterobacter cloacae. From 38% to 46% of K. pneumoniae strains were resistant to third-generation cephalosporins, but all of them were sensitive to imipenem. From 60% to 80% of E. cloacae isolates were resistant to all beta-lactams, but sensitive to imipenem. Resistance of P. aeruginosa to aminoglycosides varied from 30% for gentamicin to 5% for amikacin. About 40% of P. aeruginosa strains were resistant to carbenicillin, and 25% to azlocillin and piperacillin, but only two strains were resistant to ceftazidime and imipenem. Among Gram-positive cocci the most frequently encountered were coagulase-negative staphylococci, followed by Staphylococcus aureus and Enterococcus faecalis. The methicillin-resistant strains of coagulase-negative staphylococci and S. aureus consisted 74.8% and 34%, respectively. All strains of methicillin-resistant coagulase-negative staphylococci and S. aureus were sensitive to vancomycin.