The objective of this study was to isolate, identify, and genotype Campylobacter jejuni from various sources in the province of Kayseri, Turkey. A total of 6667 samples consisting of 5167 human fecal swabs, 600 dog rectal swabs, 600 cattle gallbladders, and 300 chicken carcasses were examined. The samples were plated onto mCCDA (cefoperazone charcoal desoxycholate agar) agar. In order to identify C. jejuni, phenotypic tests and PCR (polymerase chain reaction) were performed. C. jejuni was isolated in 1.43%, 43.50%, 31.16%, and 56% of the human, dog, cattle, and chicken samples, respectively. Among the 690 C. jejuni strains that were isolated during the study period, 200 C. jejuni strains (50 strains from each species) were randomly selected. The selected strains were typed by using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) fla-typing. DdeI and HinfI restriction enzymes were used for molecular typing. Following the DdeI enzyme application, the strains produced various numbers of bands between 4 and 7, with a total of 20 different band profiles. No similar band profiles were seen among the strains isolated from different sources. It was found that HinfI was not a more discriminative enzyme for fla-typing of C. jejuni isolates.