The aim of this study was to reveal the extended-spectrum β-lactamase (ESBL) production rates of Escherichia coli and Klebsiella spp. strains isolated from nosocomial and community-acquired infections and fecal samples of healthy people. Clinical samples such as urine, blood, abscess, wound, and sputum from inpatients and outpatients and fecal samples from healthy people were cultivated, and cultures yielding Klebsiella spp. or E. coli strains were scanned and confirmed for ESBL production phenotypically by disk diffusion method according to the Clinical Laboratory Standards Institute. Extended-spectrum β-lactamase production in E. coli and Klebsiella spp. strains isolated from clinical samples that belong to inpatients and outpatients was found in 8 (9%) of 91 strains from community-acquired infections and in 16 (28%) of 58 strains from nosocomial infections. A total of 8 (7%) of 112 strains isolated from the fecal samples of healthy people were found positive for ESBL production. It is obvious that resistant microorganisms are being challenging not only at hospitals but also in the community. In our study, ESBL production rate for the strains isolated from the fecal samples of healthy people was found very close to that for the strains isolated from the community-acquired infections. According to these results, ESBL production has already become an issue that requires measures to be taken not only in hospitals but also in the community.