The penicillin resistance of 30 Streptococcus pneumoniae strains which isolated from specimens that have been accepted to Microbiology and Clinical Microbiology Laboratory of Fırat Medical Center, were tested by using oxacillin(1g) screening test. Penicillin, ceftriaxon and cefotaxim susceptibilities of oxacillin resistant strains were determined by E test method. Erytromycin, azitromycin and cloramphenicol susceptibilities of oxacillin resistant strains were determined by disc diffusion technique. CLS guidelines were used for determination of resistant strains. There were no resistance strains against ceftriaxon and cefotaxim.7 strains were resistant against oxacillin by using disc diffusion technique. 7 strains which were resistant against oxacillin by using disc diffusion technique were mild resistant against penicillin by using E test method. 2 strains which were resistant against Penicillin were resistant against erytromycin.