Nosocomial infections have become a universal health problem and they increase the morbidity and mortality in hospitalized patients. They also pose of major financial burden for health care expenses. We analyzed the surveillance data for bacterial nosocomial infections (defined according to the Centers for Disease Control criteria) in Selçuk University Hospital which were encountered between May 1997 - January 1999. Six hundred and thirty nine episodes were recorded among 35,479 hospitalized patients( 1.8%). The distribution of these episodes according to the inpatient services were as follows Reanimation 179 (29.0 %), Pediatrics 127(19.9 %), General Surgery 80(12.5 %), Internal Medicine 63(9.8 %), Neurology 49(7.7 %), Orthopedics 42(6.6 %), Neurosurgery 38(5.9 %), Cardiothoraxic and Vascular Surgery 33(5.2 %), Respiratory Diseases 26 (4.4 %), The distribution of bacterial nosocomial infections according to site was as follows: Urinary Tract 214(33.0 %), Respiratory 210(30.0 %), Surgical Incision SiteI21(20.2 %), Skin and Soft-Tissue 58(9.8 %), Bacteriemia 26(3.6 %), Genital Tract 6(2.8 %) and Central Nervous System 4(0.5 %). The microorganisms isolated from these episodes were as follows; E. coli (20.1 %), S. aureus (18.9 %), Pseudomonas sp. (16.2 %), Enterobacter sp. (9.3 %) and Klebsiella sp (8.0%).