Campylobacter jejuni of different subtypes were identified in chicken, dairy cattle and diarrhoea patients in China from 2005 to 2006, using multiplex PCR and RFLP. The results indicated that, of the three types of samples, C. jejuni was most frequently detected in poultry of the three types of samples, with an average isolation rate of up to 18.61% and a flock contamination rate of 86.67%. The average incidence of C. jejuni in overall cattle and environmental samples, milk cows, heifers and diarrhoea patients was 7.77, 5.02, 8.70 and 4.84%, respectively. A higher prevalence was detected in outpatients than ward patients (P<0.01), and in patients aged <7 years than in older patients (P<0.01). The 265 isolates of C. jejuni were classified into 20 distinct types by PCR-RFLP analysis of the flaA gene, with the genotype distribution in humans overlapping that in poultry and cattle. This suggests that certain C. jejuni strains circulate between humans and domestic animals such as cattle and poultry.