Purpose: Streptococcus pneumoniae is a pathogen that cause significant mortality and morbidity in humans. In particular, bacteremia, pneumonia, meningitis and middle ear inflammation. S. pneumoniae can cause many diseases in children and adults. Recently, S. pneumoniae is the most important cause of acute respiratory tract diseases in developing countries. Increasing antibiotic resistance in S. pneumoniae strains has recently gained importance. The aim of our study was to investigate the antimicrobial susceptibility and distribution of pneumococcal serotypes of S. pneumoniae strains isolated in our University Hospital.