Fifty-one Campylobacter jejuni strains (thirty-five were derived from three poultry processing plants in 1998, and sixteen were from three food poisoning cases that occurred in Shiga prefecture in 1998) were examined by pulsed-field gel electrophoresis (PFGE) analysis. The SacII digest profile was compared with the result of serotyping. As PFGE was distinguishable to all strains including the untypable ones by serotyping, PFGE was more discriminatory than serotyping. Our conclusion is that PFGE will be useful for epidemiological investigation of Campylobacter jejuni strains identified untypable by serotyping.